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1.
Environ Monit Assess ; 194(2): 62, 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-34993664

RESUMO

Nine metals including Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were analysed from sediment samples collected from 29 stations since 2007 from Bahraini waters. Within this study, it was investigated whether concentrations of these determinants are at concentrations above internationally established Assessment Criteria (AC). The majority of sites were considered not to pose a toxicological risk in terms of metal contamination. Where breaches occurred, they were mainly from historic samples related to Cr, Cu and Ni contamination. A trend assessment revealed that out of 59 significant trends, 36 were downwards and 23 upwards, indicating that some determinants like Al, Zn and Ni are improving strongly across some sites, whilst areas associated with industrial activity still see some increasing trends for Al, Cd, Pb and Zn.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Barein , Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados/análise , Poluentes Químicos da Água/análise
2.
Crit Rev Toxicol ; 51(2): 183-191, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-34032188

RESUMO

Safety in use of jamu consumption, as part of traditional medicine from Indonesia, is dependent on the complete and adequate assessment of potential hazards and risks of the botanicals and botanical constituents included. This includes especially hazards and risks related to the presence in jamu of active pharmaceutical ingredients (APIs) as well as of constituents that are genotoxic and carcinogenic. The present review presents an overview of the current state-of-the art on these hazards and risks based on case reports on adulteration, and the actual detection of genotoxic and carcinogenic ingredients of concern in jamu. Based on the overview thus obtained, it appears that drug-adulteration presents important hazards responsible for potential adverse effects, due to overdosing. The potential hazards of exposure to APIs mainly relate to the presence of constituents that may cause liver damage, renal impairment, kidney failure, steroid dependence or genotoxicity and carcinogenicity. For these APIs, a risk characterisation was performed based on comparison of health-based guidance values (HBGVs) and exposure, while for the genotoxic carcinogens the margin of exposure (MOE) approach was used. Results of this risk characterisation should be used by risk managers to impose specification for constituents of health concern to protect consumers. It is concluded that to manage the risks identified and further improve the safety in use of jamu, a collaboration between farmers, manufacturer/producers, academia, government, health professionals, and consumers is indicated.


Assuntos
Suplementos Nutricionais/toxicidade , Medicina Tradicional , Carcinógenos/toxicidade , Dano ao DNA , Contaminação de Medicamentos , Humanos , Medição de Risco
3.
Regul Toxicol Pharmacol ; 123: 104936, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33905779

RESUMO

Skin sensitisation is a key adverse health effect to be addressed in the safety assessment of cosmetic ingredients. Regulatory demands have urged the development of Next Generation Risk Assessment (NGRA) using New Approach Methodologies (NAM) and Defined Approaches (DA) instead of animal models. An illustrative NGRA case study shall demonstrate if the use of propyl paraben at 0.2% in a face cream was safe for consumers. A sequential stacking tier testing DA based on NAM data predicted propyl paraben to be a non-sensitiser, while some NAM input data showed positive results. To increase confidence, structurally related parabens were considered, which revealed NAM and DA hazard predictions similar to those of propyl paraben, non-sensitiser classifications in animal models and very rare cases of human skin allergy. Based on a weight of evidence it was decided that propyl paraben should be considered a non-sensitiser leading to a favourable NGRA conclusion, in line with traditional risk assessment. Examination of an ab initio NGRA based on NAM and metabolism data resulted in a more conservative weak sensitiser consideration as point of departure, which still led to a favourable conclusion.


Assuntos
Parabenos/toxicidade , Pele/efeitos dos fármacos , Animais , Cosméticos , Dermatite Alérgica de Contato , Modelos Animais , Medição de Risco
4.
Arch Toxicol ; 94(7): 2549-2557, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32514609

RESUMO

Theoretically, both synthetic endocrine disrupting chemicals (S-EDCs) and natural (exogenous and endogenous) endocrine disrupting chemicals (N-EDCs) can interact with endocrine receptors and disturb hormonal balance. However, compared to endogenous hormones, S-EDCs are only weak partial agonists with receptor affinities several orders of magnitude lower. Thus, to elicit observable effects, S-EDCs require considerably higher concentrations to attain sufficient receptor occupancy or to displace natural hormones and other endogenous ligands. Significant exposures to exogenous N-EDCs may result from ingestion of foods such as soy-based diets, green tea and sweet mustard. While their potencies are lower as compared to natural endogenous hormones, they usually are considerably more potent than S-EDCs. Effects of exogenous N-EDCs on the endocrine system were observed at high dietary intakes. A causal relation between their mechanism of action and these effects is established and biologically plausible. In contrast, the assumption that the much lower human exposures to S-EDCs may induce observable endocrine effects is not plausible. Hence, it is not surprising that epidemiological studies searching for an association between S-EDC exposure and health effects have failed. Regarding testing for potential endocrine effects, a scientifically justified screen should use in vitro tests to compare potencies of S-EDCs with those of reference N-EDCs. When the potency of the S-EDC is similar or smaller than that of the N-EDC, further testing in laboratory animals and regulatory consequences are not warranted.


Assuntos
Exposição Dietética/efeitos adversos , Disruptores Endócrinos/efeitos adversos , Sistema Endócrino/efeitos dos fármacos , Compostos Fitoquímicos/efeitos adversos , Testes de Toxicidade , Animais , Disruptores Endócrinos/síntese química , Sistema Endócrino/metabolismo , Sistema Endócrino/fisiopatologia , Humanos , Ligantes , Medição de Risco
5.
Regul Toxicol Pharmacol ; 117: 104755, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32800849

RESUMO

Historically skin sensitisation risk assessment for cosmetic ingredients was based on animal models, however regulatory demands have led to Next Generation Risk Assessment (NGRA), using data from New Approach Methodologies (NAM) and Defined Approaches (DA). This case study was meant to investigate if the use of resorcinol at 0.2% in a face cream was safe and a maximum use concentration could be defined. The NAM data and DA predictions could not provide sufficient confidence to determine a point of departure (POD). Therefore, the application of read-across was explored to increase the level of confidence. Analogue searches in various tools and databases using "mode of action" and "chemical structural features" retrieved 535 analogues. After refinement by excluding analogues without a defined structure, similar reactivity profile and skin sensitisation data, 39 analogues remained. A final selection was made based on three approaches: expert judgment, chemical similarity or Local Lymph Node Assay data (LLNA). All read-across approaches supported a moderate potency. A POD derived from the LLNA EC3 of 3.6% was determined leading to a favourable NGRA conclusion and a maximum use concentration of 0.36%. This was supported by a traditional risk assessment based on the available animal data for resorcinol.


Assuntos
Cosméticos/efeitos adversos , Ensaio Local de Linfonodo , Resorcinóis/efeitos adversos , Creme para a Pele/efeitos adversos , Pele/efeitos dos fármacos , Animais , Cosméticos/administração & dosagem , Análise de Dados , Humanos , Resorcinóis/administração & dosagem , Medição de Risco , Pele/metabolismo , Pele/patologia , Creme para a Pele/administração & dosagem
6.
Food Chem Toxicol ; 183: 114306, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38052406

RESUMO

This study aims to analyse the risk to consumers given the presence of heavy metals and bromine in honey from different countries. A probabilistic approach was applied to assess carcinogenic risk. Concerning exposure, Al in Spain (3.3E-04 mg/kgBw/day), B in Dominican Republic and Mexico (2E-04 mg/kgBw/day in both cases) and Fe in Mexico and Mozambique had the highest values (5E-05 and 4.8E-05 mg/kgBw/day). In risk characterisation, the values were less than 1 for hazard index (HI), meaning that the consumption of honey represents a low level of concern for non-genotoxic effects. A combination of margin of exposure and probability of exceedance results that exposure to Pb pose no threat. The probability of suffering cancer for Br, Cd, Ni and Pb was lower than 1.0E-06 and, therefore, considered safe. However, the risk at the 95th percentile of Br in Dominican Republic was 1.18E-04 in adults and 2.45E-04 in children, exceeding 1.0E-04, and therefore, considered intolerable. Finally, the sensitivity analysis indicated that the most influential factor in the HI was the consumption in adults and the concentration of Ni in children, whereas for cancer risk, were the concentrations of Ni, Cd, Br and Pb, in both cases.


Assuntos
Mel , Metais Pesados , Neoplasias , Poluentes do Solo , Criança , Adulto , Humanos , Bromo/análise , Mel/análise , República Dominicana , México , Moçambique , Espanha , Cádmio/análise , Chumbo/análise , Medição de Risco , Monitoramento Ambiental/métodos , Metais Pesados/toxicidade , Metais Pesados/análise , Poluentes do Solo/análise , China
7.
Foods ; 13(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38472839

RESUMO

This study analysed the probabilistic risk to consumers associated with the presence of iAs, Cd, Cr, Hg, Pb, acrylamide (AA) and ochratoxin A (OTA) in instant coffee from Brazil, Colombia, Mexico and Peru. The results found iAs to be the metal with the highest concentrations (3.50 × 10-2 to 6.00 × 10-2 mg/kg), closely followed by Pb (1.70 × 10-2 to 2.70 × 10-2 mg/kg) and Cr (5.00 × 10-3 to 1.00 × 10-2 mg/kg), although these differences were not significant between countries. Cd and Hg were not detected. Focusing on AA, the concentrations ranged from 1.77 × 10-1 mg/kg (Peru) to 4.77 × 10-1 mg/kg (Brazil), while OTA ranged from 1.32 × 10-3 (Peru) to 1.77 × 10-3 mg/kg (Brazil) with significant differences between countries in both cases. As regards risk, the hazard quotient and hazard index were less than 1, meaning that the consumption of instant coffee represents a low level of concern for non-genotoxic effects. The results of the combination of margin of exposure and probability of exceedance indicated that the non-genotoxic effects of Pb, AA and OTA pose no threat. However, the probability values of suffering cancer from iAs and AA (between 1 × 10-6 and 1 × 10-4) indicated a moderate risk and that management measures should be taken.

8.
Food Chem Toxicol ; 187: 114598, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38493981

RESUMO

Seafood products accumulate methylmercury throughout the food chain and are the main source of methylmercury exposure. Methylmercury may trigger a number of adverse health effects, such as neurodevelopmental or nephrotoxic effects, the risk of which cannot be ruled out for the French high consumers of seafood. The characterisation of methylmercury-related risks is generally based on short-term dietary exposure without considering changes in consumption and exposure over the lifetime. Additionally, focusing on short-term dietary exposure, the fate of methylmercury (especially its accumulation) in the organism is not considered. The present study proposes a methodology basing risk characterization on estimates of body burden over a lifetime. First, trajectories of dietary exposures throughout lifetime were constructed based on the actual concentrations of total diet studies for a fictive representative French population, taking into account the social, economic and demographic parameters of individuals. Next, the fate of methylmercury in the body was estimated, based on these trajectories, using a specific physiologically-based kinetic (PBK) model that generated a representative pool of body burden trajectories. Simulated hair mercury concentrations were closed to previously reported French representative human biomonitoring data. Results showed that at certain stages of life, concentrations of methylmercury in hair were higher than the human biomonitoring guidance value set at 2.5 µg/g of hair by JECFA. This study showed the added value, in the case of substances accumulating in the body, of estimating dietary exposure over a lifetime and using exposure biomarkers estimated by a PBK model characterize the risk.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Humanos , Compostos de Metilmercúrio/toxicidade , Compostos de Metilmercúrio/análise , Alimentos Marinhos/análise , Contaminação de Alimentos/análise , Dieta , Exposição Dietética , Mercúrio/análise
9.
Regul Toxicol Pharmacol ; 67(3): 325-34, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24051162

RESUMO

In the current EU legislative frameworks on chemicals safety, the requirements with respect to information on general kinetic parameters (absorption, distribution, metabolism and excretion or ADME) or integrated toxicokinetic parameters (TK, i.e. plasma concentration-time curve, area under the curve etcetera) in humans and experimental animals vary widely. For agrochemicals and cosmetics, there are regulatory requirements whereas for other frameworks, such as food ingredients, biocides, consumer products and high production volume chemicals (REACH) there are very little or no requirements. This paper presents case studies that illustrate the importance of ADME and TK data in regulatory risk characterisations. The examples were collected by interviewing regulatory risk assessors from various chemicals (non-pharmaceutical) frameworks. The case studies illustrate how (1) applying ADME/TK in an early phase of toxicity testing can be used to improve study design and support the 3R-goals and how (2) increased use of ADME/TK data can improve the final risk assessment.


Assuntos
Qualidade de Produtos para o Consumidor/legislação & jurisprudência , Substâncias Perigosas/farmacocinética , Experimentação Humana não Terapêutica , Testes de Toxicidade , Animais , União Europeia , Regulamentação Governamental , Guias como Assunto , Substâncias Perigosas/química , Substâncias Perigosas/toxicidade , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Nível de Efeito Adverso não Observado , Experimentação Humana não Terapêutica/legislação & jurisprudência , Experimentação Humana não Terapêutica/normas , Medição de Risco , Especificidade da Espécie , Testes de Toxicidade/métodos , Testes de Toxicidade/normas
10.
Foods ; 12(20)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37893740

RESUMO

Eggs play an important role in a balanced diet; however, the European Food Safety Authority (EFSA) recognizes eggs as a major source of poly and per-fluoroalkyl substances (PFASs). In this study, the presence of PFASs was analysed in eggs produced by hens from Northern Italian regions, a PFASs-contaminated area. Sixty-five samples were analysed by high-performance liquid chromatography coupled with high-resolution mass spectrometry. The greatest presence of PFASs was found in eggs from Veneto and Emilia Romagna, and the most detected PFASs were perfluorobutanoic acid (PFBA) and perfluorooctanesulfonic acid (PFOS) (mean concentrations 0.30 ± 0.15 and 0.05 ± 0.00 ng g-1). Considering the most recent updates for the sum of the main four PFASs, the highest concentration found in the analysed samples was 0.05 ng g-1, well below the maximum limit set by the European Union. The PFAS intake evaluation confirmed that egg consumption does not represent a risk for Italian consumers.

11.
Sci Total Environ ; 859(Pt 1): 160254, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36402343

RESUMO

The study evaluated the presence and fate of various contaminants of emerging concern (CECs) from a South African wastewater treatment works (WWTW) and surface waters located around an urban setting. A total of 45 CECs were quantified from nine sampling locations over an 11-month period. Daily loads (g/day) of the target analytes in the WWTW showed persistence of some CECs, along with population-normalised daily loads (mg/day/1000inh) of pharmaceuticals and drugs of abuse (DOA) that were estimated for the first time in the study area. Multiple chemical markers were recorded in river water located upstream of the WWTW discharge throughout the study period, suggesting a high degree of diffuse pollution from urban communities in the study area that are not connected to sewage networks or where sanitation services are limited. The potential of using defined surface water locations to perform community-wide substance use profiling for non-sewered communities was also explored. Environmental risk characterisation for the WWTW effluent and surface waters throughout the study period provided multiple risk quotients (RQ) for the target list of CECs spanning over various sentinel trophic levels. High risk profiles (RQ > 1.0) with a frequency of exceedance (FoE) larger than 75 % were recorded for several CECs in both WWTW effluent and surface water locations that suggest potential long-term ecological health risk impacts of pollution hotspot areas in the river catchment situated around the urban area. We present challenges in surface water quality within the study area that is relatable, or may even present more challenging, in other low- or middle-income country (LMICs) settings. The study also highlighted some challenges and limitations associated with the much-needed application of wastewater-based epidemiology (WBE) intervention in non-sewered communities that can inform on public health and communal substance use profiles of the entire urban setting.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Rios/química , Esgotos
12.
Artigo em Inglês | MEDLINE | ID: mdl-34913854

RESUMO

Perchlorate is known as a thyroid disrupter. Its contamination in various tea samples was monitored, and 286 samples belonging to four types of tea leaves were analysed. The detection rate of perchlorate in tea was 99.3%. The mean concentration in different tea types decreased in order from green tea, oolong tea, white tea to black tea. A probabilistic approach was performed to evaluate the dietary exposure of perchlorate for six different subpopulations. The daily intakes (EDIs) for consumers over the age of 41 were higher than that of other subpopulations. The hazard quotient for six groups was lower than 1 even at the extreme percentile (P99). It indicates that the risk of dietary exposure to perchlorate from tea consumption for Fujian people is acceptable without considering other foodstuffs. However, the high occurrence of perchlorate in tea samples suggested that the actual source of this contaminant should be further investigated.


Assuntos
Exposição Dietética/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Folhas de Planta/química , Chá/química , Humanos , Método de Monte Carlo , Medição de Risco
13.
Food Chem Toxicol ; 161: 112810, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35031389

RESUMO

In 2017, a total diet study (TDS) was conducted in the Netherlands to determine the intake of elements by 1- and 2-year-old children. Concentrations of 47 elements were analysed and long-term dietary intake was calculated for 24 elements. The 95th percentile (P95) intake estimates were compared with a tolerable daily or weekly intake (TDI or TWI) or tolerable upper intake level (UL), or a margin of exposure (MOE) was calculated. The P95 intake of cadmium and zinc exceeded the TWI or UL, respectively, and the P95 intake of inorganic arsenic and lead resulted in low MOEs. Food subgroups contributing most to the intake were "potatoes" for cadmium, "milk and milk-based beverages" for zinc, "concentrated fruit juices" and "rice" for inorganic arsenic, and "candies" for lead. For inorganic mercury, it could not be established if the intake was (too) high. P95 intake estimates of the other elements for which a risk characterisation could be performed were below the health-based guidance values. It was noted that the P50 intake estimate of manganese was a factor of 3 higher than the adequate intake level. Due to the absence of a UL, it is not clear if this intake is of concern.


Assuntos
Inquéritos sobre Dietas , Ingestão de Alimentos , Análise de Alimentos , Alimentos Infantis/análise , Oligoelementos , Humanos , Lactente , Países Baixos , Medição de Risco
14.
Artigo em Inglês | MEDLINE | ID: mdl-35457502

RESUMO

The link between air pollution and health burden in urban areas has been well researched. This has led to a plethora of effective policy-induced monitoring and interventions in the global south. However, the implication of pollutant species like PM2.5 in low middle income countries (LMIC) still remains a concern. By adopting a positivist philosophy and deductive reasoning, this research addresses the question, to what extent can we deliver effective interventions to improve air quality at a building structure located at a busy road node in a LMIC? This study assessed the temporal variability of pollutants around the university environment to provide a novel comparative evaluation of occupational shift patterns and the use of facemasks as risk control interventions. The findings indicate that the concentration of PM2.5, which can be as high as 300% compared to the WHO reference, was exacerbated by episodic events. With a notable decay period of approximately one-week, adequate protection and/or avoidance of hotspots are required for at-risk individuals within a busy road node. The use of masks with 80% efficiency provides sufficient mitigation against exposure risks to elevated PM2.5 concentrations without occupational shift, and 50% efficiency with at least '2 h ON, 2 h OFF' occupational shift scenario.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/prevenção & controle , Monitoramento Ambiental , Humanos , Material Particulado/análise
15.
Chem Biol Interact ; 326: 109099, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32370863

RESUMO

Theoretically, both synthetic endocrine disrupting chemicals (S-EDCs) and natural (exogenous and endogenous) endocrine disrupting chemicals (N-EDCs) can interact with endocrine receptors and disturb hormonal balance. However, compared to endogenous hormones, S-EDCs are only weak partial agonists with receptor affinities several orders of magnitude lower. Thus, to elicit observable effects, S-EDCs require considerably higher concentrations to attain sufficient receptor occupancy or to displace natural hormones and other endogenous ligands. Significant exposures to exogenous N-EDCs may result from ingestion of foods such as soy-based diets, green tea and sweet mustard. While their potencies are lower as compared to natural endogenous hormones, they usually are considerably more potent than S-EDCs. Effects of exogenous N-EDCs on the endocrine system were observed at high dietary intakes. A causal relation between their mechanism of action and these effects is established and biologically plausible. In contrast, the assumption that the much lower human exposures to S-EDCs may induce observable endocrine effects is not plausible. Hence, it is not surprising that epidemiological studies searching for an association between S-EDC exposure and health effects have failed. Regarding testing for potential endocrine effects, a scientifically justified screen should use in vitro tests to compare potencies of S-EDCs with those of reference N-EDCs. When the potency of the S-EDC is similar or smaller than that of the N-EDC, further testing in laboratory animals and regulatory consequences are not warranted.


Assuntos
Disruptores Endócrinos/efeitos adversos , Sistema Endócrino/efeitos dos fármacos , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/efeitos adversos , Animais , Humanos
16.
Food Chem Toxicol ; 142: 111349, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32360905

RESUMO

Theoretically, both synthetic endocrine disrupting chemicals (S-EDCs) and natural (exogenous and endogenous) endocrine disrupting chemicals (N-EDCs) can interact with endocrine receptors and disturb hormonal balance. However, compared to endogenous hormones, S-EDCs are only weak partial agonists with receptor affinities several orders of magnitude lower. Thus, to elicit observable effects, S-EDCs require considerably higher concentrations to attain sufficient receptor occupancy or to displace natural hormones and other endogenous ligands. Significant exposures to exogenous N-EDCs may result from ingestion of foods such as soy-based diets, green tea and sweet mustard. While their potencies are lower as compared to natural endogenous hormones, they usually are considerably more potent than S-EDCs. Effects of exogenous N-EDCs on the endocrine system were observed at high dietary intakes. A causal relation between their mechanism of action and these effects is established and biologically plausible. In contrast, the assumption that the much lower human exposures to S-EDCs may induce observable endocrine effects is not plausible. Hence, it is not surprising that epidemiological studies searching for an association between S-EDC exposure and health effects have failed. Regarding testing for potential endocrine effects, a scientifically justified screen should use in vitro tests to compare potencies of S-EDCs with those of reference N-EDCs. When the potency of the S-EDC is similar or smaller than that of the N-EDC, further testing in laboratory animals and regulatory consequences are not warranted.


Assuntos
Exposição Dietética , Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Humanos , Medição de Risco
17.
Environ Toxicol Pharmacol ; 78: 103396, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32391796

RESUMO

Theoretically, both synthetic endocrine disrupting chemicals (S-EDCs) and natural (exogenous and endogenous) endocrine disrupting chemicals (N-EDCs) can interact with endocrine receptors and disturb hormonal balance. However, compared to endogenous hormones, S-EDCs are only weak partial agonists with receptor affinities several orders of magnitude lower. Thus, to elicit observable effects, S-EDCs require considerably higher concentrations to attain sufficient receptor occupancy or to displace natural hormones and other endogenous ligands. Significant exposures to exogenous N-EDCs may result from ingestion of foods such as soy-based diets, green tea and sweet mustard. While their potencies are lower as compared to natural endogenous hormones, they usually are considerably more potent. Effects of exogenous N-EDCs on the endocrine system were observed at high dietary intakes. A causal relation between their mechanism of action and these effects is established and biologically plausible. In contrast, the assumption that the much lower human exposures to S-EDCs may induce observable endocrine effects is not plausible. Hence, it is not surprising that epidemiological studies searching for an association between S-EDC exposure and health effects have failed. Regarding testing for potential endocrine effects, a scientifically justified screen should use in vitro tests to compare potencies of S-EDCs with those of reference N-EDCs. When the potency of the S-EDC is similar or smaller than that of the N-EDC, further testing in laboratory animals and regulatory consequences are not warranted.


Assuntos
Produtos Biológicos/toxicidade , Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Sistema Endócrino/efeitos dos fármacos , Exposição Ambiental , Hormônios , Humanos , Receptores de Esteroides/metabolismo , Medição de Risco
18.
Toxicol In Vitro ; 67: 104861, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32360643

RESUMO

Theoretically, both synthetic endocrine disrupting chemicals (S-EDCs) and natural (exogenous and endogenous) endocrine disrupting chemicals (N-EDCs) can interact with endocrine receptors and disturb hormonal balance. However, compared to endogenous hormones, S-EDCs are only weak partial agonists with receptor affinities several orders of magnitude lower. Thus, to elicit observable effects, S-EDCs require considerably higher concentrations to attain sufficient receptor occupancy or to displace natural hormones and other endogenous ligands. Significant exposures to exogenous N-EDCs may result from ingestion of foods such as soy-based diets, green tea and sweet mustard. While their potencies are lower as compared to natural endogenous hormones, they usually are considerably more potent than S-EDCs. Effects of exogenous N-EDCs on the endocrine system were observed at high dietary intakes. A causal relation between their mechanism of action and these effects is established and biologically plausible. In contrast, the assumption that the much lower human exposures to S-EDCs may induce observable endocrine effects is not plausible. Hence, it is not surprising that epidemiological studies searching for an association between S-EDC exposure and health effects have failed. Regarding testing for potential endocrine effects, a scientifically justified screen should use in vitro tests to compare potencies of S-EDCs with those of reference N-EDCs. When the potency of the S-EDC is similar or smaller than that of the N-EDC, further testing in laboratory animals and regulatory consequences are not warranted.


Assuntos
Disruptores Endócrinos/toxicidade , Exposição Ambiental , Poluentes Ambientais/toxicidade , Hormônios/metabolismo , Sistema Endócrino , Humanos , Receptores de Superfície Celular/metabolismo , Medição de Risco
19.
Environ Pollut ; 263(Pt A): 114424, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32247920

RESUMO

Natural and synthetic steroid hormones and many persistent organic pollutants are of concern for their endocrine-disrupting activities observed in receiving surface waters. Apart from the demonstrated presence of estrogen- and estrogen-mimicking compounds in surface waters, antagonistic (anti-estrogenic) responses originating from wastewater effluent have been reported but are less known. Estrogenicity and anti-estrogenicity were assessed using recombinant yeast estrogen receptor binding assays (YES/YAES) at ten South African wastewater treatment works (WWTWs) and receiving rivers in two separate sampling campaigns during the summer- and winter periods in the area. Four WWTWs were then further investigated to show daily variation in estrogenic endocrine-disrupting activities during the treatment process. Although estrogenicity was notably reduced at most of the WWTWs, some treated effluent and river water samples were shown to be above effect-based trigger values posing an endocrine-disrupting risk for aquatic life and potential health risks for humans. Furthermore, estrogenicity recorded in samples collected upstream from some WWTW discharge points also exceeded some calculated risk trigger values, which highlights the impact of alternative pollution sources contributing towards endocrine disrupting contaminants (EDCs) in the environment. The YAES further showed variable anti-estrogenic activities in treated wastewater. The current study highlights a variety of factors that may affect bioassay outcomes and conclusions drawn from the results for risk decision-making. For example, mismatches were found between estrogenic and anti-estrogenic activity, which suggests a potential masking effect in WWTW effluents and highlights the complexity of environmental samples containing chemical mixtures having variable endocrine-disrupting modes of action. Although the recombinant yeast assay is not without its limitations to show endocrine-disrupting modulation in test water systems, it serves as a cost-effective tier-1 scoping assay for further risk characterisation and intervention.


Assuntos
Disruptores Endócrinos/análise , Poluentes Químicos da Água/análise , Bioensaio , Monitoramento Ambiental , Estrogênios/análise , Humanos , Rios , Águas Residuárias
20.
EFSA J ; 18(5): e06113, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-37649524

RESUMO

The European Commission asked EFSA to update their 2006 opinion on ochratoxin A (OTA) in food. OTA is produced by fungi of the genus Aspergillus and Penicillium and found as a contaminant in various foods. OTA causes kidney toxicity in different animal species and kidney tumours in rodents. OTA is genotoxic both in vitro and in vivo; however, the mechanisms of genotoxicity are unclear. Direct and indirect genotoxic and non-genotoxic modes of action might each contribute to tumour formation. Since recent studies have raised uncertainty regarding the mode of action for kidney carcinogenicity, it is inappropriate to establish a health-based guidance value (HBGV) and a margin of exposure (MOE) approach was applied. For the characterisation of non-neoplastic effects, a BMDL 10 of 4.73 µg/kg body weight (bw) per day was calculated from kidney lesions observed in pigs. For characterisation of neoplastic effects, a BMDL 10 of 14.5 µg/kg bw per day was calculated from kidney tumours seen in rats. The estimation of chronic dietary exposure resulted in mean and 95th percentile levels ranging from 0.6 to 17.8 and from 2.4 to 51.7 ng/kg bw per day, respectively. Median OTA exposures in breastfed infants ranged from 1.7 to 2.6 ng/kg bw per day, 95th percentile exposures from 5.6 to 8.5 ng/kg bw per day in average/high breast milk consuming infants, respectively. Comparison of exposures with the BMDL 10 based on the non-neoplastic endpoint resulted in MOEs of more than 200 in most consumer groups, indicating a low health concern with the exception of MOEs for high consumers in the younger age groups, indicating a possible health concern. When compared with the BMDL 10 based on the neoplastic endpoint, MOEs were lower than 10,000 for almost all exposure scenarios, including breastfed infants. This would indicate a possible health concern if genotoxicity is direct. Uncertainty in this assessment is high and risk may be overestimated.

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