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1.
Ann Allergy Asthma Immunol ; 131(1): 89-95, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36990203

RESUMO

BACKGROUND: Allergic rhinitis affects approximately 10% to 20% of people living in industrialized nations leading to significant morbidity and large health care expenditures. Individualized high-dose, single-species allergen immunotherapy has been found to be effective in treating allergic rhinitis but can be associated with significant risks including anaphylaxis. Few studies have evaluated the safety and efficacy of universal low-dose multiallergen immunotherapy (MAIT). OBJECTIVE: To determine the efficacy and safety of a universal MAIT formula for the treatment of allergic rhinitis. METHODS: Patients with moderate-severe perennial and seasonal allergic rhinitis were randomized in a double-blind, placebo-controlled fashion to receive a novel, subcutaneous MAIT regimen containing a unique mixture of more than 150 aeroallergens, including several cross-reactive species. All patients received the exact same universal immunotherapy formula regardless of which specific skin tests were positive. Primary outcome measures at 8 and 12 weeks of therapy included validated clinical assessments, total nasal sinus score and mini-rhinoconjunctivitis quality of life questionnaire, and the use of rescue medications. RESULTS: A total of 31 patients (n = 31) were randomized to receive MAIT vs placebo. By week 12, MAIT resulted in a -4.6 (-58%) decrease in the combined total nasal sinus score and rescue medication score (daily combined score) compared with -1.5 (-20%) for placebo (P = .04). Likewise, MAIT resulted in a decrease in the mini-rhinoconjunctivitis quality of life questionnaire score of -34.9 (-68%) compared with -17 (-42%) for the placebo (P = .04). Mild adverse events were uncommon and with similar frequency among the groups. CONCLUSION: A novel, universal, and high-species abundant MAIT formula was well tolerated and resulted in significant improvement in symptoms of moderate-severe allergic rhinitis. The results of this pilot study should be considered preliminary, pending further randomized clinical trials.


Assuntos
Conjuntivite , Rinite Alérgica , Humanos , Projetos Piloto , Qualidade de Vida , Resultado do Tratamento , Dessensibilização Imunológica/métodos , Método Duplo-Cego , Conjuntivite/etiologia
2.
Environ Sci Technol ; 57(16): 6360-6372, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37036108

RESUMO

Residential buildings provide unique conditions for opportunistic premise plumbing pathogen (OPPP) exposure via aerosolized water droplets produced by showerheads, faucets, and tubs. The objective of this review was to critically evaluate the existing literature that assessed the impact of potentially enhancing conditions to OPPP occurrence associated with residential plumbing and to point out knowledge gaps. Comprehensive studies on the topic were found to be lacking. Major knowledge gaps identified include the assessment of OPPP growth in the residential plumbing, from building entry to fixtures, and evaluation of the extent of the impact of typical residential plumbing design (e.g., trunk and branch and manifold), components (e.g., valves and fixtures), water heater types and temperature setting of operation, and common pipe materials (copper, PEX, and PVC/CPVC). In addition, impacts of the current plumbing code requirements on OPPP responses have not been assessed by any study and a lack of guidelines for OPPP risk management in residences was identified. Finally, the research required to expand knowledge on OPPP amplification in residences was discussed.


Assuntos
Água Potável , Engenharia Sanitária , Abastecimento de Água , Habitação , Microbiologia da Água
3.
Environ Sci Technol ; 57(23): 8750-8759, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37255211

RESUMO

Water quality impacts of new ion exchange point-of-entry residential softeners and their ability to be decontaminated following hydrocarbon exposure were investigated. During startup, significant amounts of total sulfur (445 ± 815 mg/L) and total organic carbon (937 ± 119 mg/L) were released into the drinking water that flowed through the softeners. Particulate organic carbon was released until the third regeneration cycle, and resin may also have been released. After one week of device use, softeners continued to cause organic carbon levels to be four to five times greater than background levels. Leached materials from the ion-exchange resin contributed to chlorine decay. When resins were exposed to hydrocarbon-contaminated water, they sorbed benzene, toluene, ethylbenzene, and xylenes (BTEX) and then desorbed the contaminants into drinking water during a 15 day flushing decontamination period. On day 15, benzene exceeded the federal drinking water limit for two of the four resins. The aged resin contributed to the greatest chlorine decay rates and sorbed and then retained the least amount of BTEX. Scale and biofilm on the aged resin likely prompted disinfectant reactivity and inhibited BTEX diffusion into the resin. Study results show that softeners exposed to hydrocarbon-contaminated water may need to be repeatedly flushed to remove BTEX contamination or be replaced. Additional work is recommended to better understand softener impacts on drinking water quality.


Assuntos
Água Potável , Poluentes Químicos da Água , Benzeno/análise , Cloro , Carbono , Derivados de Benzeno , Hidrocarbonetos , Tolueno/análise , Xilenos/análise , Poluentes Químicos da Água/análise
4.
J Environ Health ; 85(4): 22-31, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37736399

RESUMO

Cured-in-place pipes (CIPPs) are plastic liners manufactured inside existing damaged sanitary sewer, storm sewer, and water pipes that extend the service life of host pipes. This process often is conducted in neighborhoods and near roadways. Before, during, and after plastic manufacture, waste materials that include volatile materials are released into the air. Emissions from this manufacturing process can affect outdoor air quality and indoor air quality for buildings connected to the sewer system. We identified key issues and solicited stakeholder feedback to estimate and manage public health risks of CIPP-generated chemical air pollution. A work group representing 13 U.S. agencies and public health associations provided feedback and prioritized public health issues for action. To mitigate potential public and occupational health risks, additional testing and public health educational efforts were recommended. An improved understanding of CIPP chemical exposure pathways, as well as stakeholder needs and interests, is essential.

5.
N Engl J Med ; 378(13): 1200-1210, 2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-29527974

RESUMO

BACKGROUND: Cardiovascular risk is increased in patients with gout. We compared cardiovascular outcomes associated with febuxostat, a nonpurine xanthine oxidase inhibitor, with those associated with allopurinol, a purine base analogue xanthine oxidase inhibitor, in patients with gout and cardiovascular disease. METHODS: We conducted a multicenter, double-blind, noninferiority trial involving patients with gout and cardiovascular disease; patients were randomly assigned to receive febuxostat or allopurinol and were stratified according to kidney function. The trial had a prespecified noninferiority margin of 1.3 for the hazard ratio for the primary end point (a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or unstable angina with urgent revascularization). RESULTS: In total, 6190 patients underwent randomization, received febuxostat or allopurinol, and were followed for a median of 32 months (maximum, 85 months). The trial regimen was discontinued in 56.6% of patients, and 45.0% discontinued follow-up. In the modified intention-to-treat analysis, a primary end-point event occurred in 335 patients (10.8%) in the febuxostat group and in 321 patients (10.4%) in the allopurinol group (hazard ratio, 1.03; upper limit of the one-sided 98.5% confidence interval [CI], 1.23; P=0.002 for noninferiority). All-cause and cardiovascular mortality were higher in the febuxostat group than in the allopurinol group (hazard ratio for death from any cause, 1.22 [95% CI, 1.01 to 1.47]; hazard ratio for cardiovascular death, 1.34 [95% CI, 1.03 to 1.73]). The results with regard to the primary end point and all-cause and cardiovascular mortality in the analysis of events that occurred while patients were being treated were similar to the results in the modified intention-to-treat analysis. CONCLUSIONS: In patients with gout and major cardiovascular coexisting conditions, febuxostat was noninferior to allopurinol with respect to rates of adverse cardiovascular events. All-cause mortality and cardiovascular mortality were higher with febuxostat than with allopurinol. (Funded by Takeda Development Center Americas; CARES ClinicalTrials.gov number, NCT01101035 .).


Assuntos
Alopurinol/efeitos adversos , Doenças Cardiovasculares/induzido quimicamente , Febuxostat/efeitos adversos , Supressores da Gota/efeitos adversos , Gota/tratamento farmacológico , Idoso , Alopurinol/uso terapêutico , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/mortalidade , Causas de Morte , Método Duplo-Cego , Febuxostat/uso terapêutico , Feminino , Gota/complicações , Supressores da Gota/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade
6.
Environ Sci Technol ; 54(18): 11453-11463, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32786341

RESUMO

When rainwater harvesting is utilized as an alternative water resource in buildings, a combination of municipal water and rainwater is typically required to meet water demands. Altering source water chemistry can disrupt pipe scale and biofilm and negatively impact water quality at the distribution level. Still, it is unknown if similar reactions occur within building plumbing following a transition in source water quality. The goal of this study was to investigate changes in water chemistry and microbiology at a green building following a transition between municipal water and rainwater. We monitored water chemistry (metals, alkalinity, and disinfectant byproducts) and microbiology (total cell counts, plate counts, and opportunistic pathogen gene markers) throughout two source water transitions. Several constituents including alkalinity and disinfectant byproducts served as indicators of municipal water remaining in the system since the rainwater source does not contain these constituents. In the treated rainwater, microbial proliferation and Legionella spp. gene copy numbers were often three logs higher than those in municipal water. Because of differences in source water chemistry, rainwater and municipal water uniquely interacted with building plumbing and generated distinctively different drinking water chemical and microbial quality profiles.


Assuntos
Água Potável , Legionella , Água Potável/análise , Chuva , Água , Microbiologia da Água , Qualidade da Água , Abastecimento de Água
7.
Inhal Toxicol ; 31(4): 131-146, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-31187656

RESUMO

Objectives: US water infrastructure is in need of widespread repair due to age-related deterioration. Currently, the cured-in-place (CIPP) procedure is the most common method for water pipe repair. This method involves the on-site manufacture of a new polymer composite plastic liner within the damaged pipe. The CIPP process can release materials resulting in occupational and public health concerns. To understand hazards associated with CIPP-related emission exposures, an in vitro toxicity assessment was performed. Materials and Methods: Mouse alveolar epithelial and alveolar macrophage cell lines and condensates collected at 3 worksites utilizing styrene-based resins were utilized for evaluations. All condensate samples were normalized based on the major emission component, styrene. Further, a styrene-only exposure group was used as a control to determine mixture related toxicity. Results: Cytotoxicity differences were observed between worksite samples, with the CIPP worksite 4 sample inducing the most cell death. A proteomic evaluation was performed, which demonstrated styrene-, worksite-, and cell-specific alterations. This examination of protein expression changes determined potential biomarkers of exposure including transglutaminase 2, advillin, collagen type 1, perilipin-2, and others. Pathway analysis of exposure-induced proteomic alterations identified MYC and p53 to be regulators of cellular responses. Protein changes were also related to pathways involved in cell damage, immune response, and cancer. Conclusions: Together these findings demonstrate potential risks associated with the CIPP procedure as well as variations between worksites regarding emissions and toxicity. Our evaluation identified biological pathways that require a future evaluation and also demonstrates that exposure assessment of CIPP worksites should examine multiple chemical components beyond styrene, as many cellular responses were styrene-independent.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Monitoramento Ambiental/métodos , Células Epiteliais/efeitos dos fármacos , Macrófagos Alveolares/efeitos dos fármacos , Manufaturas/toxicidade , Estireno/toxicidade , Animais , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Expressão Gênica/efeitos dos fármacos , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/metabolismo , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Proteoma/genética , Proteoma/metabolismo , Células RAW 264.7 , Local de Trabalho
8.
J Water Health ; 17(2): 196-203, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30942770

RESUMO

Drinking water distribution system contamination incidents can prompt public agencies and drinking water utilities to issue do-not-drink and do-not-use advisories. After the contaminant is cleared from distribution mains, consumers are often directed to flush their plumbing. However, little validated guidance and few evaluated communications strategies are available on using flushing to decontaminate building water systems. Additionally, limited data support the effectiveness of current practices and recommendations. In this study, expert elicitation was used to assess existing flushing guidance and develop validated flushing guidance and communications for single-family residences. The resulting guidance recommends progressively opening all cold-water taps from the closest to point of entry to the furthest and allowing the water to run for at least 20 minutes. Hot-water taps should be opened progressively and run for at least 75 minutes. The guidance language and format conformed to grade-level and readability scores within recommended health communication ranges. The readability of eight other flushing guidance documents was also evaluated for contamination incidents from 2008-2015. Seven were written at a 10th-12th grade level, above the 6th-7th grade level recommended for health communications.


Assuntos
Comunicação em Saúde , Engenharia Sanitária , Compreensão , Habitação , Humanos , Abastecimento de Água/estatística & dados numéricos
9.
Am Heart J ; 197: 85-93, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29447788

RESUMO

BACKGROUND: The xanthine oxidase (XO) system is a significant source of vascular oxidative stress, which is believed to impair endothelial function, an important contributor to atherosclerotic disease. We tested whether febuxostat, a potent XO inhibitor, improves coronary endothelial function (CEF) in patients with stable coronary artery disease (CAD) in a single-center, randomized, placebo-controlled, double-blind crossover trial. METHODS: CEF was measured using noninvasive magnetic resonance imaging (MRI) assessment of changes in 30 patients with stable CAD and baseline impaired CEF. Patients received either febuxostat or placebo for 6 weeks and then were crossed over to the alternative for an additional 6 weeks. MRI-detected changes in coronary flow and in coronary cross-sectional area from rest to isometric handgrip exercise, a known endothelial-dependent stressor, were measured at the end of each 6 week period. RESULTS: Mean serum urate levels were lower at the end of the 6-week febuxostat period (2.9±0.8mg/dL) than at the end of the 6-week placebo period (5.9±0.04, P<.001). However, there were no significant differences in any of the CEF parameters measured at the end of the febuxostat and placebo periods. CONCLUSIONS: In summary, although XO inhibition with febuxostat was well tolerated and lowered serum urate, it did not improve the primary end point of the study, CEF measured using MRI after 6 weeks of treatment. In conclusion, these findings suggest that short-term inhibition of XO does not significantly improve impaired CEF in patients with stable CAD.


Assuntos
Doença da Artéria Coronariana , Vasos Coronários , Endotélio Vascular , Febuxostat/administração & dosagem , Xantina Oxidase , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/metabolismo , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/fisiopatologia , Estudos Cross-Over , Método Duplo-Cego , Monitoramento de Medicamentos/métodos , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Feminino , Supressores da Gota/administração & dosagem , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Resultado do Tratamento , Xantina Oxidase/antagonistas & inibidores , Xantina Oxidase/metabolismo
10.
J Appl Toxicol ; 37(12): 1464-1470, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28653411

RESUMO

In response to the 2010 Deepwater Horizon oil spill, over 1 million gallons of dispersant were applied in Gulf of Mexico offshore waters; Corexit 9500 was the most applied dispersant. The impact on organisms in nearshore and freshwaters has received little scrutiny. Acute 48 h toxicity of Corexit 9500 and a new hyperbranched polyethylenimine (HPEI) dispersant-like compound were evaluated for the freshwater indicator organism, Daphnia magna and for larval and early spat stages of the Eastern oyster, Crassostrea virginica. For D. magna, Corexit 9500 demonstrated toxicity (EC50 of 0.14 [0.13, 0.15] ppm) similar to the 10-kDa HPEI (EC50 of 0.16 [0.12, 0.19] ppm). HPEI toxicity increased as a function of molecular weight (1.2 to 750 kDa). The 10 kDa size HPEI was further investigated because it dispersed crude oil with equal effectiveness as Corexit. For Corexit, 100% oyster mortality was detected for the ≤0.2-mm size classes and mortality >50% for the 0.3- and 0.7-mm size classes at the two greatest concentrations (25 and 50 ppm). HPEI (10 kDa) exhibited low mortality rates (<30%) for all concentrations for all oyster size classes except the 0.1-mm class. Although mortality rates for this size class were up to 60%, mortality was still less than the mortality caused by Corexit 9500. The low toxicity of HPEI polymers for C. virginica in comparison with Corexit 9500 suggests that HPEI polymers warrant further study.


Assuntos
Crassostrea/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Poluição por Petróleo/análise , Petróleo/toxicidade , Tensoativos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Crassostrea/crescimento & desenvolvimento , Daphnia/crescimento & desenvolvimento , Larva , Lipídeos/toxicidade , Polietilenoimina/toxicidade
11.
J Environ Qual ; 45(5): 1490-1500, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27695739

RESUMO

Chemical spills and accidents contaminate the environment and disrupt societies and economies around the globe. In the United States there were approximately 172,000 chemical spills that affected US waterbodies from 2004 to 2014. More than 8000 of these spills involved non-petroleum-related chemicals. Traditional emergency responses or incident command structures (ICSs) that respond to chemical spills require coordinated efforts by predominantly government personnel from multiple disciplines, including disaster management, public health, and environmental protection. However, the requirements of emergency response teams for science support might not be met within the traditional ICS. We describe the US ICS as an example of emergency-response approaches to chemical spills and provide examples in which external scientific support from research personnel benefitted the ICS emergency response, focusing primarily on nonpetroleum chemical spills. We then propose immediate, near-term, and long-term activities to support the response to chemical spills, focusing on nonpetroleum chemical spills. Further, we call for science support for spill prevention and near-term spill-incident response and identify longer-term research needs. The development of a formal mechanism for external science support of ICS from governmental and nongovernmental scientists would benefit rapid responders, advance incident- and crisis-response science, and aid society in coping with and recovering from chemical spills.


Assuntos
Acidentes , Poluentes Químicos da Água , Substâncias Perigosas , Estados Unidos
12.
Environ Sci Technol ; 49(24): 14239-48, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26554276

RESUMO

As levels of natural organic matter (NOM) in surface water rise, the minimization of potentially harmful disinfection by-products (DBPs) becomes increasingly critical. Here, we introduce the advantage that chromatographic prefractionation brings to investigating compositional changes to NOM caused by chlorination. Fractionation reduces complexity, making it easier to observe changes and attribute them to specific components. Under the conditions tested (0.1-0.4 g of Cl to g of C without further additives), the differences between highly and less oxidized NOM were striking. Highly oxidized NOM formed more diverse Cl-containing DPB, had a higher propensity to react with multiple Cl, and tended to transform so drastically as to no longer be amenable to electrospray-ionization mass spectral detection. Less-oxidized material tended to incorporate one Cl and retain its humiclike composition. N-containing, lipidlike, and condensed aromatic structure (CAS)-like NOM were selectively enriched in mass spectra, suggesting that such components do not react as extensively with NaOCl as their counterparts. Carbohydrate-like NOM, conversely, was selectively removed from spectra by chlorination.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Desinfecção/métodos , Espectrometria de Massas/métodos , Compostos Orgânicos/química , Carbono/química , Cloro/análise , Cromatografia , Halogenação , Substâncias Húmicas/análise , Concentração de Íons de Hidrogênio , Oxirredução , Raios Ultravioleta
13.
Environ Sci Technol ; 49(2): 813-23, 2015 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-25513829

RESUMO

During January 2014, an industrial solvent contaminated West Virginia's Elk River and 15% of the state population's tap water. A rapid in-home survey and water testing was conducted 2 weeks following the spill to understand resident perceptions, tap water chemical levels, and premise plumbing flushing effectiveness. Water odors were detected in all 10 homes sampled before and after premise plumbing flushing. Survey and medical data indicated flushing caused adverse health impacts. Bench-scale experiments and physiochemical property predictions showed flushing promoted chemical volatilization, and contaminants did not appreciably sorb into cross-linked polyethylene (PEX) pipe. Flushing reduced tap water 4-methylcyclohexanemethanol (4-MCHM) concentrations within some but not all homes. 4-MCHM was detected at unflushed (<10 to 420 µg/L) and flushed plumbing systems (<10 to 96 µg/L) and sometimes concentrations differed among faucets within each home. All waters contained less 4-MCHM than the 1000 µg/L Centers for Disease Control drinking water limit, but one home exceeded the 120 µg/L drinking water limit established by independent toxicologists. Nearly all households refused to resume water use activities after flushing because of water safety concerns. Science based flushing protocols should be developed to expedite recovery, minimize health impacts, and reduce concentrations in homes when future events occur.


Assuntos
Acidentes de Trabalho , Água Potável/análise , Poluentes Químicos da Água/análise , Qualidade da Água , Abastecimento de Água , Indústria Química , Meio Ambiente , Monitoramento Ambiental , Monoterpenos/química , Odorantes , Polietileno/química , Análise de Regressão , Rios , Engenharia Sanitária , Solventes , West Virginia
14.
J Water Health ; 13(4): 960-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26608758

RESUMO

The influence of four different cleaning methods used for newly installed polyethylene (PEX) pipes on chemical and odor quality was determined. Bench-scale testing of two PEX (type b) pipe brands showed that the California Plumbing Code PEX installation method does not maximize total organic carbon (TOC) removal. TOC concentration and threshold odor number values significantly varied between two pipe brands. Different cleaning methods impacted carbon release, odor, as well the level of drinking water odorant ethyl tert-butyl ether. Both pipes caused odor values up to eight times greater than the US federal drinking water odor limit. Unique to this project was that organic chemicals released by PEX pipe were affected by pipe brand, fill/empty cycle frequency, and the pipe cleaning method selected by the installer.


Assuntos
Água Potável/análise , Odorantes/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Abastecimento de Água/métodos , Polietileno , Engenharia Sanitária , Movimentos da Água
15.
Environ Sci Technol ; 48(18): 10938-47, 2014 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-25127182

RESUMO

Cured-in-place pipe (CIPP) is becoming a popular U.S. stormwater culvert rehabilitation method. Several State transportation agencies have reported that CIPP activities can release styrene into stormwater, but no other contaminants have been monitored. CIPP's stormwater contamination potential and that of its condensate waste was characterized. Condensate completely dissolved Daphnia magna within 24 h. Condensate pH was 6.2 and its chemical oxygen demand (COD) level was 36,000 ppm. D. magna mortality (100%) occurred in 48 h, even when condensate was diluted by a factor of 10,000 and styrene was present at a magnitude less than its LC50. Condensate and stormwater contained numerous carcinogenic solvents used in resin synthesis, endocrine disrupting contaminants such as plasticizers, and initiator degradation products. For 35 days, COD levels at the culvert outlets and downstream ranged from 100 to 375 ppm and styrene was 0.01 to 7.4 ppm. Although contaminant levels generally reduced with time, styrene levels were greatest 50 ft downstream, not at the culvert outlet. Cured CIPP extraction tests confirmed that numerous contaminants other than styrene were released into the environment and their persistence and toxicity should be investigated. More effective contaminant containment and cleaner installation processes must be developed to protect the environment.


Assuntos
Tempestades Ciclônicas , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Alabama , Animais , Análise da Demanda Biológica de Oxigênio , Carbono/análise , Daphnia/efeitos dos fármacos , Metais Pesados/análise , Metais Pesados/toxicidade , Estireno/análise , Estireno/toxicidade , Testes de Toxicidade , Compostos Orgânicos Voláteis/análise , Poluentes Químicos da Água/toxicidade
16.
Compr Rev Food Sci Food Saf ; 13(4): 679-692, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33412706

RESUMO

This article is one of a series of 4 that report on a task of the NanoRelease Food Additive project of the Intl. Life Science Inst. Center for Risk Science Innovation and Application to identify, evaluate, and develop methods that are needed to confidently detect, characterize, and quantify intentionally produced engineered nanomaterials (ENMs) released from food along the alimentary tract. This particular article focuses on the problem of detecting ENMs that become released into food indirectly from food contact materials. In this review, an in-depth analysis of the release literature is presented and relevant release mechanisms are discussed. The literature review includes discussion of articles related to the release phenomenon in general, as experimental methods to detect ENMs migrating from plastic materials into other (nonfood) complex matrices were determined to be relevant to the focus problem of food safety. From the survey of the literature, several "control points" were identified where characterization data on ENMs and materials may be most valuable. The article concludes with a summary of findings and a discussion of potential knowledge gaps and targets for method development in this area.

17.
Environ Sci Ecotechnol ; 18: 100314, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37854462

RESUMO

A reduction in building occupancy can lead to stagnant water in plumbing, and the potential consequences for water quality have gained increasing attention. To investigate this, a study was conducted during the COVID-19 pandemic, focusing on water quality in four institutional buildings. Two of these buildings were old (>58 years) and large (>19,000 m2), while the other two were new (>13 years) and small (<11,000 m2). The study revealed significant decreases in water usage in the small buildings, whereas usage remained unchanged in the large buildings. Initial analysis found that residual chlorine was rarely detectable in cold/drinking water samples. Furthermore, the pH, dissolved oxygen, total organic carbon, and total cell count levels in the first draw of cold water samples were similar across all buildings. However, the ranges of heavy metal concentrations in large buildings were greater than observed in small buildings. Copper (Cu), lead (Pb), and manganese (Mn) sporadically exceeded drinking water limits at cold water fixtures, with maximum concentrations of 2.7 mg Cu L-1, 45.4 µg Pb L-1, 1.9 mg Mn L-1. Flushing the plumbing for 5 min resulted in detectable residual at fixtures in three buildings, but even after 125 min of flushing in largest and oldest building, no residual chlorine was detected at the fixture closest to the building's point of entry. During the pandemic, the building owner conducted fixture flushing, where one to a few fixtures were operated per visit in buildings with hundreds of fixtures and multiple floors. However, further research is needed to understand the fundamental processes that control faucet water quality from the service line to the faucet. In the absence of this knowledge, building owners should create and use as-built drawings to develop flushing plans and conduct periodic water testing.

18.
Environ Sci Process Impacts ; 25(10): 1670-1683, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37682218

RESUMO

Air-discharged waste from commonly used trenchless technologies of sewer pipe repairs is an emerging and poorly characterized source of urban pollution. This study reports on the molecular-level characterization of the atmospherically discharged aqueous-phase waste condensate samples collected at four field sites of the sewer pipe repairs. The molecular composition of organic species in these samples was investigated using reversed-phase liquid chromatography coupled with a photodiode array detector and a high-resolution mass spectrometer equipped with interchangeable atmospheric pressure photoionization and electrospray ionization sources. The waste condensate components comprise a complex mixture of organic species that can partition between gas-, aqueous-, and solid-phases when water evaporates from the air-discharged waste. Identified organic species have broad variability in molecular weight, molecular structures, and carbon oxidation state, which also varied between the waste samples. All condensates contained complex mixtures of oxidized organics, N- and S-containing organics, condensed aromatics, and their functionalized derivatives that are directly released to the atmospheric environment during installations. Furthermore, semi-volatile, low volatility, and extremely low volatility organic compounds comprise 75-85% of the total compounds identified in the waste condensates. Estimates of the component-specific viscosities suggest that upon evaporation of water waste material would form the semi-solid and solid phases. The low volatilities and high viscosities of chemical components in these waste condensates will contribute to the formation of atmospheric secondary organic aerosols and atmospheric solid nanoplastic particles. Lastly, selected components expected in the condensates were quantified and found to be present at high concentrations (1-20 mg L-1) that may exceed regulatory limits.


Assuntos
Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Espectrometria de Massas , Água , Aerossóis/análise
19.
Environ Sci Technol Lett ; 10(2): 152-158, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36818461

RESUMO

Cured-in-place-pipe (CIPP) is an onsite plastic manufacturing technology used in the U.S. and has not been evaluated for regulatory compliance with federal air pollution laws. The practice involves the discharge of manufacturing waste into the environment. The study goal was to estimate the magnitude of volatile organic compounds (VOCs) discharged into the atmosphere for styrene and nonstyrene composite manufacture and examine low-cost air monitoring sensor reliability. Time-resolved emission analysis revealed that VOC emission was not only isolated to the thermal curing period but also occurred before and after curing. In addition to the styrene monomer, other gas-phase hazardous air pollutants regulated under the Clean Air Act were also emitted. Based on typical CIPP installations, 0.9 to 16.6 U.S. tons of emitted VOCs were estimated for styrene CIPPs, and 0.09 to 1.6 U.S. tons of emitted VOCs were estimated for nonstyrene CIPPs. Because the number and size of CIPPs manufactured in a single community can vary, the total air pollution burden will significantly differ across communities. Low-cost VOC sensors commonly utilized near CIPP manufacturing activities did not accurately quantify styrene and should not be relied upon for that purpose. Up to several thousand-fold detection differences were observed. Regulatory evaluation of CIPP air pollution and PID sensor reliability assessments are recommended.

20.
Toxicol Sci ; 193(1): 62-79, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-36912746

RESUMO

Cured-in-place pipe (CIPP) technology is increasingly being utilized to repair aging and damaged pipes, however, there are concerns associated with the public health hazards of emissions. CIPP installation involves the manufacture of a new plastic composite pipe at the worksite and includes multiple variable components including resin material, curing methods, and operational conditions. We hypothesize styrene-based composite manufacturing emissions (CMEs) will induce greater pulmonary inflammatory responses and oxidative stress, as well as neurological toxicity compared with nonstyrene CMEs. Further, these CME-toxicological responses will be sex- and time-dependent. To test the hypothesis, representative CMEs were generated using a laboratory curing chamber and characterized using thermal desorption-gas chromatography-mass spectrometry and photoionization detector. Styrene was released during staying, isothermal curing, and cooling phases of the process and peaked during the cooling phase. Male and female C57BL6/J mice were utilized to examine alterations in pulmonary responses and neurotoxicity 1 day and 7 days following exposure to air (controls), nonstyrene-CMEs, or styrene-CMEs. Serum styrene metabolites were increased in mice exposed to styrene-CMEs. Metabolic and lipid profiling revealed alterations related to CIPP emissions that were resin-, time-, and sex-dependent. Exposure to styrene-CMEs resulted in an influx of lymphocytes in both sexes. Expression of inflammatory and oxidative stress markers, including Tnfα, Vcam1, Ccl2, Cxcl2, Il6, Cxcl1, Tgfß1, Tgmt2, and Hmox1, displayed alterations following exposure to emissions. These changes in pulmonary and neurological markers of toxicity were dependent on resin type, sex, and time. Overall, this study demonstrates resin-specific differences in representative CMEs and alterations in toxicity endpoints, which can potentially inform safer utilization of composite manufacturing processes.


Assuntos
Estresse Oxidativo , Estireno , Masculino , Feminino , Camundongos , Animais , Estireno/toxicidade
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