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1.
Public Health Rep ; 136(1): 27-31, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33059533

RESUMO

An increased use of disinfectants during the coronavirus disease 2019 (COVID-19) pandemic may increase the number of adverse health effects among people who apply them or among those who are in the area being disinfected. For the 3-month period from January 1 to March 30, 2020, the number of calls about exposure to cleaners and disinfectants made to US poison centers in all states increased 20.4%, and the number of calls about exposure to disinfectants increased 16.4%. We examined calls about cleaners and disinfectants to the Michigan Poison Center (MiPC) since the onset of the COVID-19 pandemic. We compared all calls related to exposure to cleaners or disinfectants, calls with symptoms, and calls in which a health care provider was seen during the first quarters of 2019 and 2020 and in relationship to key COVID-19 dates. From 2019 to 2020, the number of all disinfectant calls increased by 42.8%, the number of calls with symptoms increased by 57.3%, the average number of calls per day doubled after the first Michigan COVID-19 case, from 4.8 to 9.0, and the proportion of calls about disinfectants among all exposure calls to the MiPC increased from 3.5% to 5.0% (P < .001). Calls for exposure to cleaners did not increase significantly. Exposure occurred at home for 94.8%97.1% of calls, and ingestion was the exposure route for 59.7% of calls. Information about the adverse health effects of disinfectants and ways to minimize exposure should be included in COVID-19 pandemic educational materials.


Assuntos
/epidemiologia , Desinfetantes/toxicidade , Centros de Controle de Intoxicações/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Michigan/epidemiologia , Pandemias
2.
Chemosphere ; 263: 128062, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297068

RESUMO

Chlorination is important to the safeness of recouped water; though it shows concern about disinfection by-products (DBPs) formation and its toxic effects. DBPs generation mostly specified by category of disinfectant utilized and naturally occurring organic matter present in the water pre and post disinfection. Plants are exposed to diverse stresses of environment across their lifespan. Reactive oxygen species (ROS) perform significant roles in preserving ordinary plant growth and enhancing their tolerance towards stress. This study is focused on the generation and elimination of ROS in apical meristematic growth and responses in Vigna radiata towards DBPs exposure. Phytotoxic and genotoxic effect of selected DBPs, TCAA (trichloroacetic acid), TCM (trichloromethane), TBM (tribromomethane) revealed concentration-dependent root length inhibition, germination index, vigour index, tolerance index, root/shoot ratio with higher EC50 value for TCM (6000 mg/L, 50.26 mM) over TCAA and TBM (1850 mg/L, 11.32 mM; 4000 mg/L, 15.83 mM). DNA laddering assay demonstrated DBP induced DNA damage to be concentration-dependent too. The concentration-dependent increase in the lipid peroxidation, H2O2 generation for each DBPs examined with highest oxidative stress for TCAA over TBM and TCM at fixed concentration illustrates that possible mechanism behind observed toxicity may be via ROS. Its regulation by antioxidative defense enzymes activities can be attributed to observed decline in these enzymes (catalase, ascorbate peroxidase, guaiacol peroxidase) activities with increasing concentration again where TCAA found more significantly affected than TBM and TCM over control. Results thus provide a useful understanding of the mechanism of DBP induced phytotoxicity and genotoxicity in V.radiata.


Assuntos
Desinfetantes , Vigna , Dano ao DNA , Desinfetantes/toxicidade , Desinfecção , Peróxido de Hidrogênio , Estresse Oxidativo , Vigna/genética
3.
Ecotoxicol Environ Saf ; 208: 111423, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33075586

RESUMO

The toxic alga Heterosigma akashiwo (Raphidophyceae) is known to form harmful algal blooms (HABs), which can have serious negative effects on the aquatic ecosystem and human life. Previous study has shown that Nω-acetylhistamine (N-AcH), an algicidal compound secreted by algicidal bacteria Bacillus sp. Strain B1, can inhibit the growth of H. akashiwo. In this study, the algicidal mechanism of N-AcH against H. akashiwo was explored, and the changes of toxicity of H. akashiwo treated with N-AcH were investigated. The algal inhibition rate was calculated by the optical density method, and the results showed that the growth inhibition rate of H. akashiwo was about 90% when treated in the medium with 40 µg/mL N-AcH at 96 h. After 72 h treatment, transmission electron microscopy (TEM) showed that the microstructure of H. akashiwo cell was seriously damaged at this concentration. The content of Chlorophyll a and Chlorophyll b decreased while malonaldehyde levels increased, and superoxide dismutase activity first increased and then decreased as well as soluble protein content. GC-MS revealed that the type and content of fatty acids cut down after 48 h and 96 h treatment. Hemolytic test, MTT assay, and micronucleus test all demonstrated the decrease in the toxicity of H. akashiwo treated with 40 µg/mL N-AcH. In brief, N-AcH mainly kills H. akashiwo cell through oxidative stress and can also reduce its toxicity, so it is a promising algicide with the dual functions of killing algae and inhibiting algal toxic effects.


Assuntos
Desinfetantes/toxicidade , Proliferação Nociva de Algas , Toxinas Marinhas/análise , Estramenópilas/efeitos dos fármacos , Bacillus , Bactérias , Clorofila A , Dinoflagelados , Ecossistema , Humanos , Malondialdeído
4.
Aquat Toxicol ; 230: 105706, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33302172

RESUMO

Triclosan, a widely used biocide broadly found in aquatic environments, is cause of concern due to its unknown effects on non-targets organisms. In this study, a multi biomarker approach was used in order to evaluate the 72 h-effect of triclosan on the freshwater alga Pseudokirchneriella subcapitata (Raphidocelis subcapitata). Triclosan, at environmental relevant concentrations (27 and 37 µg L-1), caused a decrease of proliferative capacity, which was accompanied by an increase of cell size and a profound alteration of algae shape. It was found that triclosan promoted the intracellular accumulation of reactive oxygen species, the depletion of non-enzymatic antioxidant defenses (reduced glutathione and carotenoids) and a decrease of cell metabolic activity. A reduction of photosynthetic pigments (chlorophyll a and b) was also observed. For the highest concentration tested (37 µg L-1), a decrease of photosynthetic efficiency was detected along with a diminution of the relative transport rate of electrons on the photosynthetic chain. In conclusion, triclosan presents a deep impact on the microalga P. subcapitata morphology and physiology translated by multiple target sites instead of a specific point (cellular membrane) observed in the target organism (bacteria). Additionally, this study contributes to clarify the toxicity mechanisms of triclosan, in green algae, showing the existence of distinct modes of action of the biocide depending on the microalga.


Assuntos
Clorofíceas/efeitos dos fármacos , Clorófitas/efeitos dos fármacos , Desinfetantes/toxicidade , Triclosan/toxicidade , Poluentes Químicos da Água/toxicidade , Antioxidantes/metabolismo , Clorofíceas/metabolismo , Clorofila A/metabolismo , Clorófitas/metabolismo , Desinfetantes/metabolismo , Água Doce/química , Glutationa/metabolismo , Fotossíntese/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Triclosan/metabolismo , Poluentes Químicos da Água/metabolismo
5.
Aquat Toxicol ; 230: 105717, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33307389

RESUMO

Anthropogenic changes such as ocean acidification, eutrophication, and the release of hazardous chemicals affect coastal environments and aquatic organisms. We investigated the effects of seawater pH (7.4 and 8.2) isolated and in combination with Irgarol on Ulva lactuca. Stress indicators such as membrane damage, lipid peroxidation, and hydrogen peroxide content were assessed. In addition, chlorophyll fluorescence and antioxidant enzyme activities were measured. The photosynthetic yield was affected by low pH in assays with and without Irgarol. However, the combination of low pH and Irgarol promoted photoinhibition, besides the induction of non-photochemical quenching (NPQ) and changes in photosynthetic pigment contents. The induction of NPQ was directly influenced by low pH. The membrane damage was increased in low pH with and without Irgarol exposure. Total soluble protein and carbohydrate contents decreased in low pH, and in presence of Irgarol. The H2O2 content and lipid peroxidation were not affected by low pH. In contrast, Irgarol exposure strongly increased lipid peroxidation in both pHs, suggesting a possible synergistic effect. To avoid the harmful effects of high H2O2, U. lactuca increased antioxidant enzyme activities in treatments under low pH and in presence of Irgarol. Our results indicate that U. lactuca is tolerant to low pH by inducing NPQ, changing pigment contents, and increasing antioxidant defenses. In contrast, these protective mechanisms could not avoid the harmful effects of the combination with Irgarol.


Assuntos
Antioxidantes/metabolismo , Desinfetantes/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Água do Mar/química , Triazinas/toxicidade , Ulva/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Oceano Atlântico , Brasil , Eutrofização , Peróxido de Hidrogênio/metabolismo , Concentração de Íons de Hidrogênio , Fotossíntese/efeitos dos fármacos , Ulva/metabolismo
6.
Water Res ; 188: 116549, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33152588

RESUMO

The UV/chlorine process is efficient for the abatement of micropollutants; yet, the formation of disinfection by-products (DBPs) and the toxicity can be altered during the treatment. This study investigated effluent organic matter characterization, DBP formation and toxicity alteration after the UV/chlorine treatment of wastewater; particularly, typical water matrix components in wastewater, namely, ammonia and bromide, were studied. The raw wastewater contained low levels of ammonia (3 µM) and bromide (0.5 µM). The UV/chlorine treatment efficiently eliminated 90 - 94% of fluorescent components. Compared with chlorination alone, a 20 min UV/chlorine treatment increased the formation of trihalomethanes (THMs), haloacetic acids (HAAs), chloral hydrate (CH), haloacetonitriles (HANs), trichloronitromethane (TCNM) and haloacetamides (HAcAms) by 90 - 508%. In post-chlorination after the UV/chlorine treatment, the formation of CH, HANs, TCNM and HAcAms increased by 77 - 274%, whereas the formation of both THMs and HAAs increased slightly by 11%. Meanwhile, the calculated cytotoxicity and genotoxicity of DBPs increased considerably after the UV/chlorine treatment and in post-chlorination, primarily due to the increased formation of HAAs and nitrogenous DBPs (N-DBPs). However, the acute toxicity of the wastewater to Vibrio fischeri and genotoxicity determined by the umu test decreased by 19% and 76%, respectively, after the 20 min UV/chlorine treatment. An additional 200 µM ammonia decreased the formation of all detected DBPs during the UV/chlorine treatment and 24 h post-chlorination, except that TCNM formation increased by 11% during post-chlorination. The acute toxicity of wastewater spiked with 200 µM ammonia was 32% lower than that of raw wastewater after the UV/chlorine treatment, but the genotoxicity was 58% higher. The addition of 1 mg/L bromide to the UV/chlorine process dramatically increased the formation of brominated DBPs and the overall calculated cytotoxicity and genotoxicity of DBPs. However, the acute toxicity and genotoxicity of the wastewater decreased by 7% and 100%, respectively, when bromide was added to the UV/chlorine treatment. This study illuminated that UV/chlorine treatment can decrease acute and geno- toxicities of wastewater efficiently.


Assuntos
Desinfetantes , Poluentes Químicos da Água , Purificação da Água , Amônia , Brometos , Cloro , Desinfetantes/toxicidade , Desinfecção , Halogenação , Águas Residuárias , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
7.
Environ Pollut ; 268(Pt A): 115784, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33120346

RESUMO

Systemic toxicity, particularly, developmental defects of humidifier disinfectant chemicals that have caused lung injuries in Korean children, remains to be elucidated. This study evaluated the mechanisms of the adverse effects of 5-chloro-2-methyl-4-isothiazoline-3-one/2methyl-4-isothiazolin-3-one (CMIT/MIT), one of the main biocides of the Korean tragedy, and identify the most susceptible developmental stage when exposed in early life. To this end, the study was designed to analyze several endpoints (morphology, heart rate, behavior, global DNA methylation, gene expressions of DNA methyl-transferases (dnmts) and protein profiling) in exposed zebrafish (Danio rerio) embryos at various developmental stages. The results showed that CMIT/MIT exposure causes bent tail, pericardial edema, altered heart rates, global DNA hypermethylation and significant alterations in the locomotion behavior. Consistent with the morphological and physiological endpoints, proteomics profiling with bioinformatics analysis suggested that the suppression of cardiac muscle contractions and energy metabolism (oxidative phosphorylation) were possible pivotal underlying mechanisms of the CMIT/MIT mediated adverse effects. Briefly, multi-level endpoint analysis indicated the most susceptible window of exposure to be ≤ 6 hpf followed by ≤ 48 hpf for CMIT/MIT. These results could potentially be translated to a risk assessment of the developmental exposure effects to the humidifier disinfectants.


Assuntos
Desinfetantes , Lesão Pulmonar , Animais , Criança , Desinfetantes/toxicidade , Embrião não Mamífero , Humanos , Proteômica , Peixe-Zebra
8.
Arh Hig Rada Toksikol ; 71(3): 261-264, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33074170

RESUMO

All COVID-19 prevention strategies include regular use of surface disinfectants and hand sanitisers. As these measures took hold in Croatia, the Croatian Poison Control Centre started receiving phone calls from the general public and healthcare workers, which prompted us to investigate whether the risk of suspected/symptomatic poisonings with disinfectants and sanitisers really increased. To that end we compared their frequency and characteristics in the first half of 2019 and 2020. Cases of exposures to disinfectants doubled in the first half of 2020 (41 vs 21 cases in 2019), and exposure to sanitisers increased about nine times (46 vs 5 cases in 2019). In 2020, the most common ingredients of disinfectants and sanitisers involved in poisoning incidents were hypochlorite/glutaraldehyde, and ethanol/isopropyl alcohol, respectively. Exposures to disinfectants were recorded mostly in adults (56 %) as accidental (78 %) through ingestion or inhalation (86 %). Fortunately, most callers were asymptomatic (people called for advice because they were concerned), but nearly half reported mild gastrointestinal or respiratory irritation, and in one case severe symptoms were reported (gastrointestinal corrosive injury). Reports of exposure to hand sanitisers highlighted preschool children as the most vulnerable group. Accidental exposure through ingestion dominated, but, again, only mild symptoms (gastrointestinal or eye irritation) developed in one third of the cases. These preliminary findings, however limited, confirm that increased availability and use of disinfectants and sanitisers significantly increased the risk of poisoning, particularly in preschool children through accidental ingestion of hand sanitisers. We therefore believe that epidemiological recommendations for COVID-19 prevention should include warnings informing the general public of the risks of poisoning with surface and hand disinfectants in particular.


Assuntos
2-Propanol/toxicidade , Infecções por Coronavirus/prevenção & controle , Desinfetantes/toxicidade , Etanol/toxicidade , Glutaral/toxicidade , Higienizadores de Mão/toxicidade , Ácido Hipocloroso/toxicidade , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus , Criança , Pré-Escolar , Infecções por Coronavirus/epidemiologia , Croácia/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/epidemiologia , Adulto Jovem
9.
PLoS One ; 15(10): e0241218, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33104726

RESUMO

Occupational exposure to toxic chemicals increases the risk of developing localized provoked vulvodynia-a prevalent, yet poorly understood, chronic condition characterized by sensitivity to touch and pressure, and accumulation of mast cells in painful tissues. Here, we topically sensitized female ND4 Swiss mice to the common household and industrial preservative methylisothiazolinone (MI) and subsequently challenged them daily with MI or acetone and olive oil vehicle on the labiar skin. MI-challenged mice developed significant, persistent tactile sensitivity and long-lasting local accumulation of mast cells alongside early, transient increases in CD4+ and CD8+ T cells, eosinophils, neutrophils, and increases in pro-inflammatory cytokines. Therapeutic administration of imatinib, a c-Kit inhibitor known to inhibit mast cell survival, led to reduced mast cell accumulation and alleviated tactile genital pain. We provide the first pre-clinical evidence of dermal MI-induced mast-cell dependent pain and lay the groundwork for detailed understanding of these intersections between MI-driven immunomodulation and chronic pain.


Assuntos
Dor Crônica/etiologia , Dermatite de Contato/etiologia , Desinfetantes/toxicidade , Inflamação/etiologia , Tiazóis/toxicidade , Animais , Feminino , Inflamação/imunologia , Mastócitos/imunologia , Camundongos , Pele/efeitos dos fármacos , Pele/patologia
10.
Ecotoxicol Environ Saf ; 206: 111116, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32890921

RESUMO

Disinfectant quaternary ammonium compounds (Quats) have diverse uses in a variety of consumer and commercial products, particularly cleaning products. With the emergence of the COVID-19 pandemic, they have become a primary tool to inactivate the SARS-CoV-2 virus on surfaces. Disinfectant Quats have very low vapor pressure, and following the use phase of the products in which they are found, disposal is typically "down-the-drain" to wastewater treatment systems. Consequently, the potential for the greatest environmental effect is to the aquatic environment, from treated effluent, and potentially to soils, which might be amended with wastewater biosolids. Among the earliest used and still common disinfectant Quats are the alkyl dimethyl benzyl ammonium chloride (ADBAC) compounds and the dialkyl dimethyl ammonium chloride (DDAC) compounds. They are cationic surfactants often found in consumer and commercial surface cleaners. Because of their biocidal properties, disinfectant Quats are heavily regulated for human and environmental safety around the world. Consequently, there is a robust database of information regarding the ecological hazards and environmental fate of ADBAC and DDAC; however, some of the data presented are from unpublished studies that have been submitted to and reviewed by regulatory agencies (i.e., EPA and European Chemicals Agency) to support antimicrobial product registration. We summarize the available environmental fate data and the acute and chronic aquatic ecotoxicity data for freshwater species, including algae, invertebrates, fish, and plants using peer-reviewed literature and unpublished data submitted to and summarized by regulatory agencies. The lower limit of the range of the ecotoxicity data for disinfectant Quats tends to be lower than that for other surface active agents, such as nonionic or anionic surfactants. However, ecotoxicity is mitigated by environmental fate characteristics, the data for which we also summarize, including high biodegradability and a strong tendency to sorb to wastewater biosolids, sediment, and soil. As a result, disinfectant Quats are largely removed during wastewater treatment, and those residues discharged in treated effluent are likely to rapidly bind to suspended solids or sediments, thus mitigating their toxicity.


Assuntos
Desinfetantes/toxicidade , Compostos de Amônio Quaternário/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/efeitos dos fármacos , Biodegradação Ambiental , /prevenção & controle , Desinfetantes/química , Desinfetantes/farmacologia , Ecotoxicologia , Humanos , Pandemias/prevenção & controle , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/farmacologia , Medição de Risco , Águas Residuárias/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/farmacologia , Purificação da Água/métodos
11.
Ecotoxicol Environ Saf ; 205: 111291, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956865

RESUMO

The purpose of this study was to determine the acute toxicity in aquatic organisms of one biocidal active substance and six metabolites derived from biocidal active substances and to assess the suitability of available QSAR models to predict the obtained values. We have reported the acute toxicity in sewage treatment plant (STP) microorganisms, in the freshwater microalgae Pseudokirchneriella subcapitata and in Daphnia magna following OECD test methods. We have also identified in silico models for acute toxicity of these trophic levels currently available in widely recognized platforms such as VEGA and the OECD QSAR ToolBox. A total of six, four and two models have been selected for Daphnia, algae and microorganisms, respectively. Finally, we have compared the in silico and in vivo data for the seven compounds plus two previously assayed biocidal substances. None of the compounds tested were toxic for Daphnia and STP microorganisms. For microalgae, CGA71019 (1,2,4 triazole) presented an ErC50 value of 38.3 mg/L. The selected in silico models have provided lower EC50 values and are therefore more conservative. Models from the OECD QSAR ToolBox predicted values for 7 out of 9 and for 4 out of 9 chemicals for Daphnia and P. subcapitata, respectively. No predictive models were identified in such platform for STP microorganism's acute effects. In terms of models's specificity, biocide-specific models, developed from curated datasets integrated by biocidal active substances and implemented in VEGA, perform better in the case of microalgae but for Daphnia an alternative, non biocide-specific has revealed a better performance. For STP microorganisms only biocide-specific models have been identified.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Desinfetantes/toxicidade , Modelos Biológicos , Poluentes Químicos da Água/toxicidade , Animais , Clorofíceas/efeitos dos fármacos , Simulação por Computador , Daphnia/efeitos dos fármacos , Desinfetantes/química , Desinfetantes/metabolismo , Água Doce/química , Microalgas/efeitos dos fármacos , Relação Quantitativa Estrutura-Atividade , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo
12.
Chemosphere ; 254: 126890, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957290

RESUMO

Chlorine disinfection inactivates pathogens in drinking water, but meanwhile it causes the formation of halogenated disinfection byproducts (DBPs), which may induce adverse health effects. Humans are unavoidably exposed to halogenated DBPs via tap water ingestion. Boiling of tap water has been found to significantly reduce the concentrations of halogenated DBPs. In this study, we found that compared with boiling only, adding ascorbate (vitamin C) or carbonate (baking soda) to tap water and then boiling the water further reduced the level of total organic halogen (a collective parameter for all halogenated DBPs) by up to 36% or 28%, respectively. Adding ascorbate removed the chlorine residual in tap water and thus prevented the formation of more halogenated DBPs in the boiling process. Adding carbonate elevated pH of tap water and consequently enhanced the hydrolysis (dehalogenation) of halogenated DBPs or led to the formation of more trihalomethanes that might volatilize to air during the boiling process. The comparative developmental toxicity of the DBP mixtures in the water samples was also evaluated. The results showed that adding a tiny amount of sodium ascorbate or carbonate (2.5-5.0 mg/L) to tap water followed by boiling for 5 min reduced the developmental toxicity of tap water to a substantially lower level than boiling only. The addition of sodium ascorbate or carbonate to tap water in household could be realized by preparing them in tiny pills. This study suggests simple and effective methods to reduce the adverse effects of halogenated DBPs on humans through tap water ingestion.


Assuntos
Desinfetantes/toxicidade , Poluentes Químicos da Água/toxicidade , Ácido Ascórbico , Carbonatos , Cloro , Desinfetantes/análise , Desinfecção/métodos , Água Potável/química , Halogenação , Halogênios , Humanos , Trialometanos/análise , Volatilização , Poluentes Químicos da Água/análise , Purificação da Água/métodos
13.
Environ Pollut ; 267: 115474, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32889516

RESUMO

Disinfection means the killing of pathogenic organisms (e.g. bacteria and its spores, viruses, protozoa and their cysts, worms, and larvae) present in water to make it potable for other domestic works. The substances used in the disinfection of water are known as disinfectants. At municipal level, chlorine (Cl2), chloramines (NH2Cl, NHCl2), chlorine dioxide (ClO2), ozone (O3) and ultraviolet (UV) radiations, are the most commonly used disinfectants. Chlorination, because of its removal efficiency and cost effectiveness, has been widely used as method of disinfection of water. But, disinfection process may add several kinds of disinfection by-products (DBPs) (∼600-700 in numbers) in the treated water such as Trihalomethanes (THM), Haloacetic acids (HAA) etc. which are detrimental to the human beings in terms of cytotoxicity, mutagenicity, teratogenicity and carcinogenicity. In water, THMs and HAAs were observed in the range from 0.138 to 458 µg/L and 0.16-136 µg/L, respectively. Thus, several regulations have been specified by world authorities like WHO, USEPA and Bureau of Indian Standard to protect human health. Some techniques have also been developed to remove the DBPs as well as their precursors from the water. The popular techniques of DBPs removals are adsorption, advance oxidation process, coagulation, membrane based filtration, combined approaches etc. The efficiency of adsorption technique was found up to 90% for DBP removal from the water.


Assuntos
Desinfetantes , Água Potável , Poluentes Químicos da Água , Purificação da Água , Cloro , Desinfetantes/análise , Desinfetantes/toxicidade , Desinfecção , Água Potável/análise , Halogenação , Trialometanos/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
14.
Antimicrob Resist Infect Control ; 9(1): 129, 2020 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-32771064

RESUMO

OBJECTIVES: Hand sanitisers are urgently needed in the time of COVID-19, and as a result of shortages, some people have resorted to making their own formulations, including the repurposing of distilleries. We wish to highlight the importance of those producing hand sanitisers to avoid methylated spirits containing methanol and to follow WHO recommended formulations. METHODS: We explore and discuss reports of methanol toxicity through ingestion and transdermal absorption. We discuss the WHO formulations and explain the rationale behind the chosen ingredients. SHORT CONCLUSION: We advise those producing hand sanitisers to follow WHO recommended formulations, and advise those producing hand sanitisers using methylated spirits, to avoid formulations which contain methanol.


Assuntos
Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/prevenção & controle , Desinfetantes/farmacologia , Etanol/farmacologia , Metanol/farmacologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Betacoronavirus/fisiologia , Infecções por Coronavirus/virologia , Desinfetantes/química , Desinfetantes/normas , Desinfetantes/toxicidade , Composição de Medicamentos , Etanol/química , Desinfecção das Mãos/instrumentação , Humanos , Metanol/química , Metanol/toxicidade , Pneumonia Viral/virologia , Organização Mundial da Saúde
15.
Artigo em Inglês | MEDLINE | ID: mdl-32668774

RESUMO

In recent years, peracetic acid (PAA) has gained a lot of attention as an alternative disinfectant to chlorine-based disinfectants in the water industry. Commercial PAA solutions contain both PAA and hydrogen peroxide (HP), and the degradation of HP is slower than PAA when it is used for disinfection. All previous toxicity studies have been based on commercial PAA, and variance in toxicity values have been observed due to different PAA:HP ratios. In this study, the ecotoxicity of pure PAA was studied, eliminating HP from the commercial PAA mixture using potassium permanganate. Ecotoxicity data were obtained by conducting a battery of ecotoxicity tests: bioassays using Vibrio fischeri (V. fischeri), Daphnia magna (D. magna), and Pseudokirchneriella subcapitata (P. subcapitata). The effect concentration (EC50) of pure PAA was 0.84 (a 95% confidence interval of 0.78-0.91) mg/L for V. fischeri and 2.46 (2.35-2.58) mg/L for P. subcapitata, whereas the lethal concentration (LC50) was 0.74 (0.55-0.91) mg/L for D. magna. Compared to this, our previous study found that the EC50 values of commercial PAA towards V. fischeri and P. subcapitata were 0.42 (0.41-0.44) and 1.38 (0.96-1.99) mg/L, respectively, which were lower than pure PAA, whilst the LC50 for D. magna was 0.78 (0.58-0.95) mg/L. These results showed that pure PAA was less toxic to the most commonly used aquatic species for toxicity tests compared to commercial PAA, except for D. magna.


Assuntos
Desinfetantes , Ácido Peracético , Poluentes Químicos da Água , Aliivibrio fischeri , Animais , Daphnia , Desinfetantes/toxicidade , Peróxido de Hidrogênio/toxicidade , Ácido Peracético/toxicidade , Poluentes Químicos da Água/toxicidade
16.
Aquat Toxicol ; 225: 105525, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32629302

RESUMO

Halogenated dipeptides, 3, 5-di-I-tyrosylalanine (DIYA), have been identified as novel disinfection byproducts (DBPs), following chloramination of authentic water. However, little is known about their toxicity. Zebrafish embryos were used to assess the toxicity of novel iodinated DBPs (I-DBPs). Although DIYA did not exhibit high acute toxicity to embryonic zebrafish (LC50 > 2 mM), it significantly inhibited pigmentation of melanophores and xanthophores on head, trunk and tail at 500 µM as determined by photographic analysis. Whereas N-phenylthiourea (PTU) as a pigment inhibitor did not inhibit development of yellow pigments. Colorimetric detection of melanin further confirmed these results. Quantitative real time polymerase chain reaction (qRT-PCR) measurements indicated that genes (dct, slc24a5, tyr, tyrp1a, tyrp1b, silva) associated with the melanogenesis pathway were dramatically down-regulated following exposure to 500 µM DIYA. In addition, enzymatic activity of tyrosinase (TYR) decreased, also demonstrating that the underlying mechanism of hypopigmentation was attributed to the disruption of melanogenesis pathway. Transcription levels of xanthophore genes (gch2, bnc2, csf1a, csf1b, pax7a and pax7b) were also monitored by qRT-PCR assay. DIYA exposure up-regulated expression of gch2 and bnc2, but not csf1 and pax7. Tested DIYA analogues, brominated tyrosine was unlikely to inhibit pigmentation, indicating that the iodine substitution and dipeptides structure are of important structural feature for the inhibition of pigmentation. In this study, we observed that DIYA inhibited melanogenesis related genes, which might contribute to pigmentation defects. Moreover, as an emerging I-DBPs, the developmental toxicity of aromatic dipeptides should be further studied.


Assuntos
Dipeptídeos/toxicidade , Desinfetantes/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Hipopigmentação/induzido quimicamente , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Animais , Embrião não Mamífero/metabolismo , Expressão Gênica/efeitos dos fármacos , Halogenação , Hipopigmentação/genética , Melanóforos/efeitos dos fármacos , Melanóforos/metabolismo , Purificação da Água , Proteínas de Peixe-Zebra/genética
17.
Chemosphere ; 256: 127171, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32470743

RESUMO

Freshwater ecosystems are vulnerable to residual concentrations of chemical agents from anthropogenic activities, and the real impacts of such compounds can only be evaluated accurately using ecotoxicological tests. The assessment of ecotoxicological effects of peracetic acid (PAA) and the active chlorine of calcium hypochlorite (Ca(ClO)2) on the insect Chironomus xanthus Meigen (Diptera: Chironomidae) is highly relevant as there are few reports on its effects in fresh water ecosystems. To our best knowledge, this is the first study to assess the chronic toxicity of the compounds to C. xanthus. The toxicity bioassays for C. xanthus included the acute effect (CL50) and the chronic effects based on body length, head width, and cumulative emergence. The results obtained in the acute effect tests indicated that the active chlorine of Ca(ClO)2 is 14 fold more toxic than PAA to C. xanthus. In sublethal evaluations, the active chlorine of Ca(ClO)2 presented higher toxicity than PAA in terms of percentage emergence, body development, and head width. In general, the results showed lower PAA toxicity relative to the active chlorine of Ca(ClO)2, demonstrating that PAA is a promising substitute for chlorinated disinfectants. In addition, the study facilitates the establishment of reference values for the safe release of effluents treated with PAA into water bodies.


Assuntos
Compostos de Cálcio/toxicidade , Chironomidae/efeitos dos fármacos , Cloro/toxicidade , Desinfetantes/toxicidade , Ácido Peracético/toxicidade , Animais , Cloretos , Ecossistema , Ecotoxicologia/métodos , Água Doce/química , Halogenação
18.
Chemosphere ; 252: 126611, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32443275

RESUMO

Halogenated disinfection byproducts (DBPs) are formed during chlorine disinfection of drinking water. The complicated natural organic matter in source water causes the formation of an even more complicated mixture of DBPs. To evaluate the toxicity of a DBP mixture in a disinfected water sample, the sample needs to be pretreated in order to attain an observable acute adverse effect in the toxicity test. During sample pretreatment, volatile DBPs including trihalomethanes, haloacetonitriles and haloketones may be lost, which could affect the toxicity evaluation of the DBP mixture. In this study, we intentionally prepared "concentrated" simulated drinking water samples, which contained sufficiently high levels of volatile and nonvolatile DBPs and thus enabled directly evaluating the toxicity of the DBP mixtures without sample pretreatment. Specifically, the natural organic matter and bromide concentrations and the chlorine dose in the concentrated water samples were 250 times higher than those in a typical drinking water sample. Each concentrated water sample was divided into two aliquots, and one of them was nitrogen sparged to eliminate volatile DBPs; then, both aliquots were used directly in a well-established developmental toxicity test. No significant difference (p > 0.10) was found between the developmental toxicity indexes of each concentrated water sample without and with nitrogen sparging, indicating that the contribution of volatile DBPs to the developmental toxicity of the DBP mixture might be marginal. A reasonable interpretation is that nonvolatile halogenated DBPs (especially the aromatic ones) in the DBP mixture could be the major developmental toxicity contributor that warrants more attention.


Assuntos
Desinfetantes/toxicidade , Água Potável/química , Poluentes Químicos da Água/toxicidade , Animais , Brometos , Cloro , Desinfetantes/análise , Desinfecção , Halogenação , Nitrogênio , Poliquetos/fisiologia , Trialometanos/análise , Poluentes Químicos da Água/análise , Purificação da Água
19.
Environ Mol Mutagen ; 61(6): 588-601, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32374889

RESUMO

Water disinfection, primarily by chlorination, is one of the greatest achievements of public health. However, more than half a century after its introduction, studies in the 1970s reported that (a) chlorine interacted with organic matter in the water to form disinfection by-products (DBPs); (b) two DBPs, chloroform and bromoform, both trihalomethanes (THMs), were rodent carcinogens; (c) three brominated THMs were mutagenic; in six studies chlorinated drinking waters in the United States and Canada were mutagenic; and (d) in one epidemiological study there was an association between bladder cancer mortality and THM exposure. This led the U.S. Environmental Protection Agency to issue its first DBP regulation in 1979. Forty years later, >600 DBPs have been characterized, 20/22 have been shown to be rodent carcinogens, >100 have been shown to be genotoxic, and 1000s of water samples have been found to be mutagenic. Data support a hypothesis that long-term dermal/inhalation exposure to certain levels of the three brominated THMs, as well as oral exposure to the haloacetic acids, combined with a specific genotype may increase the risk for bladder cancer for a small but significant population group. Improved water-treatment methods and stricter regulations have likely reduced such risks over the years, and further reductions in potential risk are anticipated with the application of advanced water-treatment methods and wider application of drinking water regulations. This 40-year research effort is a remarkable example of sustained cooperation between academic and government scientists, along with public/private water companies, to find answers to a pressing public health question.


Assuntos
Desinfecção/métodos , Água Potável/análise , Purificação da Água/métodos , Animais , Aniversários e Eventos Especiais , Carcinógenos/análise , Carcinógenos/toxicidade , Cloro/análise , Cloro/toxicidade , Desinfetantes/análise , Desinfetantes/toxicidade , Desinfecção/legislação & jurisprudência , Água Potável/efeitos adversos , Água Potável/legislação & jurisprudência , Halogenação , Humanos , Neoplasias/induzido quimicamente , Saúde Pública , Trialometanos/análise , Trialometanos/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Purificação da Água/legislação & jurisprudência
20.
Environ Health Perspect ; 128(5): 57006, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32438832

RESUMO

BACKGROUND: Chlorination is globally used to produce of safe drinking water. Chlorination by-products are easily formed, and there are indications that these are associated with adverse reproductive outcomes. OBJECTIVES: We conducted a nationwide register-based prospective study to assess whether gestational exposure to the four most common chlorination by-products [total trihalomethanes (TTHMs)] via tap water was associated with risk of small for gestational age (SGA), preterm delivery, and very preterm delivery. To date, this is one of the largest studies assessing drinking water TTHM-associated adverse reproductive outcomes. METHODS: We included all singleton births 2005-2015 (live and stillbirths) of mothers residing in Swedish localities having >10,000 inhabitants, ≤2 operating waterworks, adequate information on chlorination treatment, and a sufficient number of routine TTHM measurements in tap water. Individual maternal second and third trimester exposure was obtained by linking TTHM measurements to residential history, categorized into no chlorination, <5, 5-15, and >15µg TTHM/L. Outcomes and covariates were obtained via the linkage to Swedish health and administrative registers. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by logistic regression using inverse probability weighting. We stratified the analyses by chlorination treatment (chloramine, hypochlorite). RESULTS: Based on approximately 500,000 births, we observed a TTHM dose-dependent association with increased risk of SGA, confined to treatment with hypochlorite, corresponding to a multivariable-adjusted OR=1.20 (95% CI: 1.08, 1.33) comparing drinking water TTHM >15µg to the unexposed. Similar results were obtained when, instead of unexposed, the lowest exposure category (<5µg/L TTHM) was used as reference. No clear associations were observed for preterm delivery and very preterm delivery. DISCUSSION: Chlorination by-products exposure via drinking water was associated with increased risk of SGA in areas with hypochlorite treatment. https://doi.org/10.1289/EHP6012.


Assuntos
Desinfetantes/toxicidade , Água Potável/química , Desenvolvimento Fetal/efeitos dos fármacos , Exposição Materna/estatística & dados numéricos , Nascimento Prematuro/epidemiologia , Purificação da Água/métodos , Adulto , Desinfecção , Feminino , Halogenação , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Modelos Logísticos , Razão de Chances , Gravidez , Terceiro Trimestre da Gravidez , Estudos Prospectivos , Trialometanos/toxicidade , Poluentes Químicos da Água , Abastecimento de Água
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