US Environmental Protection Agency Guidelines Research Articles

Human health risk assessment of metals and arsenic via consumption of commercial bivalves in the Gulf of California, Mexico.

Although various studies have reported the bioaccumulation of metals in bivalves of commercial interest from the Gulf of California (GC), the risk associated with their consumption remains poorly understood. In this study, our own and bibliographic concentrations of 14 elements in 16 species of bivalves from 23 locations were used to investigate (1) the species-specific and regional accumulation of metals and arsenic in bivalves, (2) the human health risks by age and sex, and (3) the maximum allowable consumption rates (CRlim). The assessments were done according to the US Environmental Protection Agency guidelines. The results indicate that the bioaccumulation of elements varies markedly between groups (oysters > mussels > clams) and localities (higher on Sinaloa due to intense anthropogenic activities). However, consuming bivalves from the GC remains safe for human health. To prevent health effects for residents or consumers on the GC, we recommend (1) following the CRlim proposed herein; (2) monitoring levels of Cd, Pb, and As (inorganic) in bivalves, as the elements of top concern, mainly when are consumed by children; (3) calculating CRlim for more species and locations, including at least: As, Al, Cd, Cu, Fe, Mn, Pb, and Zn; and (4) determine the regional consumption rates of bivalves.

Fouling reduction in nanofiltration membranes in the treatment of municipal sewage - effect of coagulant type used for prior chemically enhanced primary treatment.

The limiting factor in wide-scale application of membranes for wastewater treatment is membrane fouling. Coagulation has emerged as an effective technique for fouling control. In this research, municipal wastewater was treated using a two-stage treatment. In stage-1, chemically enhanced primary treatment (CEPT) was rendered using an optimum dose of two coagulants, i.e. alum, ferric chloride and a 1:1 mix of both. The optimum doses for coagulants were determined using ajar test. In stage-2, a nanofiltration (NF) membrane was used to further treat the effluent from stage-1. In CEPT, the 1:1 mixture of coagulants showed maximum removals, i.e. 75-77% for the total suspended solids and 73-75% for the chemical oxygen demand (COD). Stage-2 provided 85-95% removals for turbidity (0.88 nephelometric turbidity units), COD (41 mg/L), total dissolved solids (101 mg/L), hardness (11 mg/L as CaCO3), chlorides (80 mg/L), and heavy metals (copper [0.03 mg/L] and lead [0.02 mg/L]). The operational time of the NF membrane was 46 min, 55 min and 70 min using alum, ferric chloride, and mix (1:1), respectively. Significant reduction was observed in membrane fouling for 1:1 mixture of coagulants. The effluent met the US Environmental Protection Agency guidelines for non-potable reuse.

Carcinogenic risk assessment and changes in Spirometric indices in casting and welding workers exposed to Metal fumes.

The aim of this study was to investigate exposure to dust, and metal fumes, changes in pulmonary function indices among industrial workers to estimate the carcinogenic and non-carcinogenic risk of exposure to occupational metal fume.<br /><br />Methods: This cross-sectional study was performed on 98 workers exposed to metal fumes. Air sampling was performed according to the NIOSH 0500 method and was analyzed by gravimetry and metal levels were analyzed by atomic absorption spectrometry. Spirometric results for 2010-2016 were collected. Carcinogenic and non-carcinogenic risk assessments were performed according to the US Environmental Protection Agency guidelines. Data were analyzed by SPSS 20 software. The mean occupational exposure of the subjects to workplace dust and iron fumes was 15.95 ± 6.65 mg/m3 and 13.18 ± 3.06 mg/m3 respectively. During these 6 years, the FVC (P=0.04), PEFR (P=0.04), and FEV1 (P=0.03) indices decreased significantly among welders, but there was no significant difference between FEV1/ FVC indexes. Also, the mean of FEV1 and PEFR decreased significantly amongst casting workers, but FVC and FEV1/ FVC had no significant difference. Multivariate regression showed that in both jobs, BMI and work history were related to pulmonary function indices. The mean total excess ifetime carcinogenic risk (ELCR) of hexavalent chromium in the study population was 0.708 per 1000 people and the mean non-carcinogenic risk of hexavalent chromium was HQ = 19.62. The results showed that exposure to metal fumes in casting and welding jobs reduces pulmonary function indices. Although the average occupational exposure to hexavalent chromium is lower than the recommended limit and the risk of carcinogenesis is within an acceptable range, the risk of non-carcinogenic effects among workers is significant Therefore, it is important to prevent this problem, by adequate ventilation and using respiratory masks.

Estimation of Cadmium in Muscles of Five Freshwater Fish Species from Manzalah Lake, and Possible Human Risk Assessment of Fish Consumption (Egypt)

The Egyptian government devised a plan in 2016 to improve the unique ecological significance of northern lakes, which mentioned Manzalah Lake in the Egypt Vision 2030. In this regard, this study investigated cadmium (Cd) content in five freshwater fish species collected from Manzalah Lake in Egypt at 2018 by local fishermen. According to the findings, Clarias gariepinus recorded the highest concentration of Cd (1.40 ± 0.2 μg/g) and the lowest concentration was recorded in O. aureus (1.19 ± 0.2 μg/g). Cadmium contents of all species were largely above the permissible level of the Food Agricultural Organization (FAO)/World Health Organization (WHO) and Commission Regulation (EC). The estimated daily intake (EDI), the estimated weekly intake (EWI), and the percentages of provisional tolerable weekly intake (PTWI %) values for Cd in the C. gariepinus > Sarotherodon galilaeus > Tilapia zillii > Oreochromis niloticus > Oreochromis aureus which consumed by children, teenagers, and adults were much higher than the PTWI values established by FAO/WHO. In addition, C. gariepinus consumed by children showed the highest value of the target hazard quotient (THQ) (5.83 a day or 40.81 a week) while O. aureus that ingested by adults showed the lowest level (1.06 a day or 7.42a week). The target carcinogenic risk (TCR) of C. gariepinus in children had the greatest level (2.21 × 10−3 a day or 1.55 × 10−2 a week), whereas O. aureus in adults had the lowest level of TCR (4 × 10−4 a day or 2.81 × 10−3 a week). THQs values of Cd in the five studied species were found higher than one. Moreover, TCRs values of Cd in the five species were exceeded the US Environmental Protection Agency guideline USEPA permissible limits suggesting that a daily or weekly consumption of these species could lead to a high risk non-carcinogenic and carcinogenic for humans.

An Assessment of Heavy Metal Contamination in the Nakdong River Around the Weir

In this study, the concentrations and characteristics of copper (Cu), zinc (Zn), and lead (Pb) contamination in sediment samples were investigated using aqua regia extraction and Tessier’s five-step sequential extraction. Based on the concentration of metals, the influence of the Hapcheon-Changnyeong weir on sediments in the Nakdong River was assessed. The origins of the contaminants, their bioavailability, and their mobility were determined using sequential extraction. Greater concentrations of heavy metals were found in samples collected closer to the weir. The largest proportion of Cu was identified in the residual fraction based on sequential extraction, whereas Zn was predominantly found in the reducible fraction. Iron-manganese in the reducible fraction of Zn has the potential to leach back to the water body. In addition, the combined concentration of fractions 1 and 2 of Cu comprised more than 20% of total amount that still has potential to affect the water quality. The results of this study were compared with existing sediment standards set out by the NIER (National Institute of Environmental Research), Canada, and US EPA (United States Environmental Protection Agency) guidelines, as well as the risk assessment code (RAC). The concentrations of heavy metals exceeded the standards set by the Canadian guideline by up to four times in particular samples, highlighting the need for continual monitoring.

Risk Assessment of Metal(Loid)s Exposed to Infants via Consumption of Weaning Foods from Different Supermarkets in Sheffield, UK.

Infant complementary foods are readily available in the UK markets and nowadays, weaning mothers prefer feeding their babies with these products due to modern lifestyles. However, there is a dearth of research with respect to the health risk assessment of trace essential and potentially toxic elements in these products. Hence, this research investigated the health risks of trace essential and potentially toxic elements exposed to infants via consumption of these complementary foods during the first 4 to 12months of life. Levels of trace essential and potentially toxic elements were determined using inductively coupled plasma mass spectrometer, daily intakes were estimated using the Food Agricultural Organization/World Health Organization and manufacturer food consumption regime while the US Environmental Protection Agency guideline was used to estimate target hazard quotient and carcinogenic health risk indices. The levels of the elements in the foods varied and were within the safe limits recommended by food standard agencies. The results also showed that the estimated daily intakes of these elements were below the reference doses stipulated by food regulatory agencies. The target hazard quotients and the total carcinogenic risks of the elements in the infant foods were less than 1 and 1.0E-04, respectively, signifying that the target groups may not experience adverse non-carcinogenic and carcinogenic health effects because of these foods. This study will be quite helpful for weaning mothers, infant food production and processing companies and government officials in taking protective measures for reducing elemental contamination in infants' complementary foods.

Furo[3,2-c]coumarin-derived Fe3+ Selective Fluorescence Sensor: Synthesis, Fluorescence Study and Application to Water Analysis

Furocoumarin (furo[3,2-c]coumarin) derivatives have been synthesized from single step, high yielding (82–92%) chemistry involving a 4-hydroxycoumarin 4 + 1 cycloaddition reaction. They are characterized by FTIR, 1H-NMR, and, for the first time, a comprehensive UV-Vis and fluorescence spectroscopy study has been carried out to determine if these compounds can serve as useful sensors. Based on the fluorescence data, the most promising furocoumarin derivative (2-(cyclohexylamino)-3-phenyl-4H-furo[3,2-c]chromen-4-one, FH), exhibits strong fluorescence (ФF = 0.48) with long fluorescence lifetime (5.6 ns) and large Stokes’ shift, suggesting FH could be used as a novel fluorescent chemosensor. FH exhibits a highly selective, sensitive and instant turn-off fluorescence response to Fe3+ over other metal ions which was attributed to a charge transfer mechanism. Selectivity was demonstrated against 13 other competing metal ions (Na+, K+, Mg2+, Ca2+, Mn2+, Fe2+, Al3+, Ni2+, Cu2+, Zn2+, Co2+, Pb2+ and Ru3+) and aqueous compatibility was demonstrated in 10% MeOH-H2O solution. The FH sensor coordinates Fe3+ in a 1:2 stoichiometry with a binding constant, Ka = 5.25 × 103 M−1. This novel sensor has a limit of detection of 1.93 µM, below that of the US environmental protection agency guidelines (5.37 µM), with a linear dynamic range of ~28 (~2–30 µM) and an R2 value of 0.9975. As an exemplar application we demonstrate the potential of this sensor for the rapid measurement of Fe3+ in mineral and tap water samples demonstrating the real-world application of FH as a “turn off” fluorescence sensor.

Pollution Intensity Assessment of Sediments Obtained Near Ieodo Ocean Research Station Using Pollution Index for Heavy Metals

Objectives:The purpose of this study was to evaluate the heavy metal contamination level by analyzing heavy metals in sediments near Ieodo ocean research station located in southwestern Jeju Island. Methods:Sixteen sediments samples were collected from Ieodo ocean research station, and two and three sediment samples were collected from the southwestern region and between Ieodo and Jeju Island. These samples were used for heavy metal content analysis according to the marine pollution process test method, and contamination level of sediments was calculated using the measured heavy metal concentration. Results and Discussion:All heavy metals except Ni were evaluated as non-contamination level, and Ni was found to have high pollution level. According to the US Environmental Protection Agency guideline, samples 6, 9, 15, and 22 were classified as severe contamination, and according to the geoaccumulation index, samples 15 and 22 were classified as slightly contaminated for Ni. When classified by the Enrichment factor value, Ni contamination was categorized as moderately severe enrichment for samples 15 and 22. Using the potential ecological risk factor value, the ecological risks of the heavy metals in all samples were classified as low risk. The mean PEL quotient value for all six heavy metals in samples was a maximum of 0.60, indicating a 21% probability of toxicity for heavy metals in all samples.Conclusions:It was confirmed that there was no contamination by Cd, Cr, Cu, Pb, and Zn, but contamination by Ni was found to be a serious level. Compared with previous studies, the concentration of Ni in the Ieodo was found to be high, which may be due to the inflow of ocean research station or the Yangzu river runoff in China.

Sun exposure and health safety practices of high school students in an urban population of Iran

BackgroundSkin cancer attributed to sunlight exposure has an increasing trend worldwide, resulting in increased problems for healthcare services. This study aimed to evaluate the health safety practices of high school students in Saveh, Iran according to a sun protection guideline produced locally for Iran.MethodThis cross-sectional study was done in 31 government and private high schools of Saveh, a central city of Iran. A sun protection questionnaire was designed in accordance with Iran sun protection guideline which has been developed based on the World Health Organization and US Environmental Protection Agency guidelines. The questionnaire consists of four sections of demographic information, knowledge, attitude, and protection behavior. A total of 504 students were selected by simple random sampling method. Pearson correlation coefficient and multiple linear regression analysis were used to assess the correlation between knowledge, attitude and behavior of the participants.ResultsThe mean score of the students’ knowledge, attitude, and behavior regarding harmfulness of ultraviolet radiation was 50.79 ± 14.64, 60.41 ± 15.04, and 45 ± 11.59, respectively. A significant association was observed between attitude and knowledge, behavior and knowledge as well as attitude. There was a significant correlation between sex and protective behaviors, sex and knowledge (p ≤ 0.001), and education level and knowledge (p = 0.002).Conclusionstudents who protected themselves from sunlight less than others believed that their protection level was adequate. Health concerns related to sun exposure suggest the need for increasing the student’s awareness in sun protection area. As behavior is influenced by cultural aspects, implementation of the current guideline can be effective in reducing the health effects of sun exposure.

Long-term effects and recovery of streams from acid mine drainage and evaluation of toxic metal threshold ranges for macroinvertebrate community reassembly.

Monitoring of benthic invertebrates in streams receiving acidic metal-contaminated water over an 18-yr period revealed both degraded conditions and recovery along a network of downstream locations. Compared with reference streams, and over the course of clean-up remediation efforts below an abandoned open-pit sulfur mine in the central Sierra Nevada of California, improving water quality was accompanied by recovery of benthic communities at some sites. Years of high flow resulted in degraded biological status when acid mine drainage capture was incomplete and metal loading had increased with runoff. Seasonal patterns of recovery evident in the fall after the summer treatment season reverted in the next spring after overwinter periods when sources were not captured. As the metal load has been reduced, phased recovery of community structure, function, and similarity progressed toward that of reference assemblage taxonomic composition. From impacted communities dominated by relatively tolerant midges, reassembly involved an increase in density, return of long-lived taxa, an increased ratio of sensitive-to-tolerant forms, then overall diversity and community composition, and eventually large predators and grazers reappearing along with mayfly, stonefly, and caddisfly richness. Threshold effect levels defined using several analysis methods showed that the response range of biological indicators corresponds to US Environmental Protection Agency guidelines of predicted effects utilizing cumulative criterion units (CCUs) of metal toxicity (i.e., CCU ∼ 1). All sites have shown improved function with increased density of some or all trophic groups over time. Although recovery is progressing, year-around treatment may be necessary to fully restore biological integrity in streams nearest the mine. Environ Toxicol Chem 2018;37:2575-2592. © 2018 SETAC.

Activated carbon fiber filters could reduce the risk of surgical smoke exposure during laparoscopic surgery: application of volatile organic compounds.

Generation of smoke is inevitable during surgical procedures. Some volatile organic compounds (VOCs) in surgical smoke are known to be strong carcinogens. We used a prototype of a multi-layered complex filter in an attempt to eliminate VOCs. From June 2015 to July 2015, 20 patients underwent transperitoneal laparoscopic nephrectomy for renal cell carcinoma. Smoke (pre-filter) was collected 20min after the electrocautery device was first used during the surgery, by the direct collection method, with a 5-L Tedlar® gas-sampling bag. Twenty and 120min after the filter was applied, smoke (post-filter) was again collected using the same method. The sample was analyzed by gas chromatography and mass spectrography. The cancer risk and hazard quotient were analyzed based on US Environmental Protection Agency guidelines. Twenty patients with a median age of 54.5 (30-80) years were enrolled in the study. Eighteen VOCs were detected using the Japanese indoor air standards mix analysis. The total elimination rate of the VOCs was 86.49 ± 2.83%. The post-filter (120min) cancer risk (mean ± standard deviation) reduced to a negligible level for benzene, ethylbenzene, and styrene except 1,2-dichloroethane. The post-filter (120min) hazard quotient for each compound decreased to levels posing a negligible risk for acetone, hexane, benzene, toluene, p-xylene, o-xylene, and styrene. Strong carcinogens, such as 1,2-dichloroethane, benzene, and ethylbenzene, were eliminated by more than 85% by using this activated carbon fiber filter and the risks from these compounds decreased to an almost negligible level. We suggest using every measure, including these filters, to protect the health of operating room personnel.

Derivation of a no-significant-risk-level for tetrabromobisphenol A based on a threshold non-mutagenic cancer mode of action.

A no‐significant‐risk‐level of 20 mg day–1 was derived for tetrabromobisphenol A (TBBPA). Uterine tumors (adenomas, adenocarcinomas, and malignant mixed Müllerian) observed in female Wistar Han rats from a National Toxicology Program 2‐year cancer bioassay were identified as the critical effect. Studies suggest that TBBPA is acting through a non‐mutagenic mode of action. Thus, the most appropriate approach to derivation of a cancer risk value based on US Environmental Protection Agency guidelines is a threshold approach, akin to a cancer safe dose (RfDcancer). Using the National Toxicology Program data, we utilized Benchmark dose software to derive a benchmark dose lower limit (BMDL10) as the point of departure (POD) of 103 mg kg–1 day–1. The POD was adjusted to a human equivalent dose of 25.6 mg kg–1 day–1 using allometric scaling. We applied a composite adjustment factor of 100 to the POD to derive an RfDcancer of 0.26 mg kg–1 day–1. Based on a human body weight of 70 kg, the RfDcancer was adjusted to a no‐significant‐risk‐level of 20 mg day–1. This was compared to other available non‐cancer and cancer risk values, and aligns well with our understanding of the underlying biology based on the toxicology data. Overall, the weight of evidence from animal studies indicates that TBBPA has low toxicity and suggests that high doses over long exposure durations are needed to induce uterine tumor formation. Future research needs include a thorough and detailed vetting of the proposed adverse outcome pathway, including further support for key events leading to uterine tumor formation and a quantitative weight of evidence analysis.

Development of biotic ligand model-based freshwater aquatic life criteria for lead following us environmental protection agency guidelines.

The US Environmental Protection Agency's (USEPA's) current ambient water quality criteria (AWQC) for lead (Pb) in freshwater were developed in 1984. The criteria are adjusted for hardness, but more recent studies have demonstrated that other parameters, especially dissolved organic carbon (DOC) and pH, have a much stronger influence on Pb bioavailability. These recent studies have been used to support development of a biotic ligand model (BLM) for Pb in freshwater, such that acute and chronic Pb toxicity can be predicted over a wide range of water chemistry conditions. Following USEPA guidelines for AWQC development and using a methodology consistent with that used by the USEPA in developing its recommended BLM-based criteria for copper in 2007, we propose acute and chronic BLM-based AWQC for Pb in freshwater. In addition to the application of the BLM approach that can better account for site-specific Pb bioavailability, the toxicity data sets presented are much more robust than in 1984, and there are now sufficient chronic Pb toxicity data available that use of an acute-to-chronic ratio is no longer necessary. Over a range of North American surface waters with representative water chemistry conditions, proposed acute BLM-based Pb criteria ranged from approximately 20 to 1000 μg/L and chronic BLM-based Pb criteria ranged from approximately 0.3 to 40 μg/L. The lowest criteria were for water with low DOC (1.2 mg/L), pH (6.7), and hardness (4.3 mg/L as CaCO3), whereas the highest criteria were for water with high DOC (9.8 mg/L), pH (8.2), and hardness (288 mg/L as CaCO3 ). Environ Toxicol Chem 2017;36:2965-2973. © 2017 SETAC.

Efficiency of Effluent Treatment Plants and Threat to Human Health and Aquatic Environment in Bangladesh

Bangladesh is a low-lying riverine country. It has about 230 small and large rivers and a large portion of the country's 140 million people depends on them for a living and for transportation. Most of the rivers and canals are becoming increasingly polluted from industrial wastewater dumped by factories, many of them in the textile, leather tanneries, pulp and paper, pharmaceutical, engineering workshops as well as chemicals and pesticide industry. Nonetheless, the wastewaters discharged from them are harshly ruinous to the environment, contains various kinds of contaminant which contaminate the water bodies, aquatic sediments, soil and ultimately incorporated into the muscles of fish, vegetables, etc. Many researchers have tried to find out the percentages of a contaminant available in different rivers and their effect on agriculture, environment and human health. Some of their research on discharging industrial wastewater quality, but none of them find out, the effectiveness of industrial effluent treatment plants. The emphasis of this research is to give a detail indication of the discharging contaminants from the five experimental industries and their effluent treatment plants (ETP). Most of our experimental industrial effluent treatment plants were able to reduce their physical parameter (BOD, COD, TSS, TDS, TS, turbidity, pH and EC) in moderate stages and two or three industry effluents were below the standard discharge limit prescribed by the Environmental Protection Agency (EPA), Bangladesh and their effluents were unsuitable for discharging into water bodies, but these are not fulfilled the US EPA guideline ranges. Whereas most of our experimental industries effluent treatment plants reduce small or less portions of metal content from their effluent which were not follow the EPA, Bangladesh and US EPA guideline ranges. They discharge their effluents into water bodies because of the lacking of a very efficient and economic treatment system.

Headspace in-tube microextraction coupled with micellar electrokinetic chromatography of neutral aromatic compounds

Headspace (HS) extraction can be carried out easily and aptly via single drop microextraction coupled with capillary electrophoresis (CE). However, one drawback is the difficulty of keeping the single drop stably at the capillary tip. To solve this problem, we have recently demonstrated HS in-tube microextraction (ITME) of acidic compounds such as chlrophenols in an acidic sample using a basic run buffer plug in the separation capillary for CE as an acceptor phase. In this report, an organic acceptor plug in a capillary was used to extract neutral organic volatile pollutants such as BTEX (benzene, toluene, ethylbenzene, and m-xylene). After extraction, the analytes enriched in the organic acceptor plug were analyzed with micellar electrokinetic chromatography (MEKC). The enrichment factors for BTEX in a standard solution were up to 350 under an optimal condition of 25°C for 20min. As an application, BTEX spiked into bottled water were analyzed with HS-ITME-MEKC, and the enrichment factors for BTEX were up to 320. The limits of detections were 1–4ppb, which are at least 200 times lower than the US Environmental Protection Agency guidelines for drinking water, except benzene. The entire procedure of HS-ITME-MEKC was carried out automatically using a commercial CE instrument.

Proposed USEPA guidelines make pollinators more prominent in pesticide considerations

Aiming to protect honeybees and wild pollinators, the U.S. Environmental Protection Agency (USEPA) is adjusting its guidelines for the use of more than 70 pesticides. Earn 0.5 CEUs in Integrated Pest Management by reading this article and completing the quiz at www.certifiedcropadviser.org/certifications/self‐study/740.

Assessment of Carcinogenic Risk and Non-Carcinogenic Health Hazard from Exposure to Toxicants in Water from the Southwestern Coastal River System in Ghana

ABSTRACTThis study evaluated cancer risk and non-cancer human health hazard from exposure to the toxicants such as As, Cu, Pb, Zn, Mn, and CN in water from a southwestern river system in Ghana that drains through gold mining areas, using 108 water samples collected with random sampling techniques and analyzed in accordance with standard methods of chemical analysis outlined by the U.S. Environmental Protection Agency (USEPA). The concentrations of Cu and Zn were within World Health Organization and USEPA guideline values; Mn, free cyanide, As, and Pb values in most cases either exceeded USEPA and WHO values or both. The concentrations of the toxicants were used as input parameters in the cancer and non-cancer study that was conducted in line with USEPA risk assessment guidelines. The results of As cancer health risk revealed higher risk cases in two locations (Potroase and Dominase); non-cancer health risk for As was higher in 10 of the 14 locations, with other metals being of health concern at few locations in the study area. In conclusion, the findings of this study hold several policy implications as residents of mining communities still depend on these water bodies as their source of drinking water.

Determination of volatile organic compounds and associated health risk assessment in residential homes and hostels within an academic institute, New Delhi

The purpose of this study was to investigate the concentrations of volatile organic compounds (VOCs) in different indoor microenvironments of residential homes and hostels in an academic institute, in New Delhi, during March-May 2011. Eleven VOCs (aromatic and halogenated) were assessed. Sampling and analytical procedure were based on National Institute for Occupational Safety and Health (NIOSH) standard method. The lifetime cancer and non-cancer risk were calculated for targeted VOCs using US Environmental Protection Agency guidelines. The mean concentrations of ∑ VOCs (sum of monitored VOCs) and individual VOC were found to be higher indoors as compared to outdoors at both types of premises. Indoor to outdoor (I/O) ratios of the targeted VOCs exceeded 1.0, suggesting the significant presence of indoor sources. Strong correlations between I/O concentrations of VOCs in the current study suggest the presence of common sources. Factor analysis (FA) was used for source evaluation separately at two premise types. The estimated lifetime cancer risks in the current study for all occupants at both premises exceeded 10(-6) .

Surgical smoke may be a biohazard to surgeons performing laparoscopic surgery

Surgical smoke production is inevitable during surgical procedures. Although many workplaces have adopted smoke-free environments, healthcare workers, especially surgeons, continue to be exposed to surgical smoke. From February 2013 to March 2013, a total of 20 patients underwent transperitoneal laparoscopic nephrectomy for renal cell carcinoma. A 5-L gas sample was collected 30min after the electrocautery device was first used and was analyzed by gas chromatography and mass spectrometry. Cancer risk was calculated for carcinogenic compounds and hazard quotient was calculated for noncarcinogenic compounds using US Environmental Protection Agency guidelines. Twenty patients with a median age of 57.5years were enrolled in the study. Eighteen volatile organic compounds were detected by Japanese indoor air standards mix analysis. The cancer risks were ethanol, 5.10×10(-5)±6.35×10(-5); 1,2-dichloroethane, 4.75×10(-3)±7.42×10(-4); benzene, 1.09×10(-3)±4.33×10(-4); ethylbenzene, 2.87×10(-5)±1.32×10(-5); and styrene, 2.94×10(-6)±1.16×10(-6). The hazard quotients were acetone, 1.88×10(-2)±7.63×10(-3); hexane, 1.48×10(-1)±8.70×10(-2); benzene, 4.66±1.85; toluene, 2.61×10(-2)±7.23×10(-3); p-xylene, 1.81×10(-1)±6.45×10(-2); o-xylene, 2.40×10(-2)±3.33×10(-2); and styrene, 5.15×10(-3)±2.03×10(-3). For five carcinogenic compounds detected, the cancer risk was greater than negligible. For 1,2-dichloroethane and benzene, the risk was classified as unacceptable. Analysis of noncarcinogenic compounds showed that risk reduction measures are needed for benzene. Even though surgical smoke is not an immediate health hazard, operating room personnel should be aware of the potential long-term health risks associated with exposure.

Anogenital distance and its application in environmental health research

Anogenital distance (AGD), a useful anthropometric measurement for genital development in both animals and humans, was originally found by reproductive toxicologists in rodent experiments. As an easy-to-measure and sensitive marker, AGD has become a bioassay of fetal androgen action and a well-established reproductive toxicity endpoint in animals. It is generally accepted that AGD is sexually dimorphic in many mammals, with males having longer AGD than females. Exposure to proposed endocrine disruptors may result in reduced AGD; thus, it has been used to measure health effects of compounds with endocrine-altering properties or endocrine-disrupting chemicals (EDCs) in environmental toxicology. Moreover, AGD is an important clinical measure to address endocrine-sensitive endpoints in the first year of life and to assess the adverse impact of in utero exposure to environmental EDCs. Recently, AGD has been identified as one of the endpoints in the US Environmental Protection Agency guidelines for reproductive toxicity studies in humans, but use of AGD in human studies is still rare, and the results remain mixed and inconclusive due to many reasons. In order to achieve a breakthrough, researchers are endeavoring to standardize the measurement of AGD, normalize age-specific population data in different ethnic groups, and conduct more in-depth human researches in this field.