Chloroform Exposure Research Articles

Subchronic Chloroform Exposure Causes Intestinal Damage and Induces Gut Microbiota Disruption and Metabolic Dysregulation in Mice.

Chloroform is a prevalent toxic environmental pollutant in urban settings, posing risks to human health through exposure via various mediums such as air and tap water. The gut microbiota plays a pivotal role in maintaining host health. However, there is a paucity of research elucidating the impact of chloroform exposure on the gut microbiota. In this investigation, 18 SPF Kunming female mice were stratified into three groups (n = 6) and subjected to oral gavage with chloroform doses equivalent to 0, 50, and 150 mg/kg of body weight over 30 days. Our findings demonstrate that subchronic chloroform exposure significantly perturbs hematological parameters in mice and induces histopathological alterations in cecal tissues, consequently engendering marked disparities in the functional composition of cecal microbiota and metabolic equilibrium of cecal contents. Ultimately, our investigation revealed a statistically robust correlation, exhibiting a high degree of significance, between the intestinal microbiome composition and the metabolites that were differentially expressed consequent to chloroform exposure.

A Rapidly Self-Healing Superhydrophobic Coating Made of Polydimethylsiloxane and N-nonadecane: Stability and Self-Healing Capabilities

Superhydrophobic surfaces have garnered significant attention in various industrial applications, such as photovoltaic power generation, anti-icing, and corrosion resistance, due to their exceptional water-repellent properties. However, the poor durability of conventional superhydrophobic coatings has severely impeded their practical implementation. To achieve the dual self-recovery of microscale and nanoscale surface structures and maintain low surface energy after damage to superhydrophobic coatings, thereby enhancing their durability, a rapidly self-healing superhydrophobic coating was developed using polydimethylsiloxane (PDMS) and n-nonadecane in this study. The coating surface demonstrated exceptional hydrophobic characteristics, as evidenced by a water contact angle (WCA) of 157.5° and a sliding angle (SA) of 4.2° achieved at optimized proportions. Through scanning electron microscopy, it was observed that the coating surface exhibited a rough structure at both the microscale and nanoscale. The stability test results showed that the WCA only decreases by 5.7° and the SA only increases by 3.6° after 100 instances of external friction. The stability test results demonstrated that the superhydrophobic coating maintains excellent hydrophobicity under mechanical external forces and in acidic and alkaline environments. The results of the self-healing capability test showed that the WCA rebounded to 151.5° and 149.5° after we subjected the samples to 20 MPa of vertical pressure damage and chloroform exposure for 4 h, respectively. The coating regained a robust hydrophobic state even after experiencing repeated mechanical and chemical damage. The above results indicate that the resulting coating demonstrates outstanding durability, including high resistance to friction, stability against acids and alkalis, and the ability to self-recover hydrophobicity after repeated damage.

On Effect of Chloroform on Electrical Activity of Proteinoids.

Proteinoids, or thermal proteins, produce hollow microspheres in aqueous solutions. Ensembles of the microspheres produce endogenous spikes of electrical activity, similar to that of neurons. To make the first step toward the evaluation of the mechanisms of such electrical behaviour, we decided to expose proteinoids to chloroform. We found that while chloroform does not inhibit the electrical oscillations of proteinoids, it causes substantial changes in the patterns of electrical activity. Namely, incremental chloroform exposure strongly affects proteinoid microsphere electrical activity across multiple metrics. As chloroform levels rise, the spike potential drops from 0.9 mV under control conditions to 0.1 mV at 25 mg/mL. This progressive spike potential decrease suggests chloroform suppresses proteinoid electrical activity. The time between spikes, the interspike period, follows a similar pattern. Minimal chloroform exposure does not change the average interspike period, while higher exposures do. It drops from 23.2 min under control experiments to 3.8 min at 25 mg/mL chloroform, indicating increased frequency of the electrical activity. These findings might lead to a deeper understanding of the electrical activity of proteinoids and their potential application in the domain of bioelectronics.

93 Chloroform exposure in air and water in Swedish indoor swimming pools - urine as a biomarker of occupational exposure

93 Chloroform exposure in air and water in Swedish indoor swimming pools - urine as a biomarker of occupational exposure

Physicochemical Characterization of Novel Bacteriophages of Pseudomonas syringe from Northwest Iran.

Bacterial canker, caused by Pseudomonas syringae, is a devastating disease of stone fruit trees worldwide. The bacterium has a broad host range and a high capacity for adaptation and dissemination, owing to its high mutation rate and horizontal gene transfer. Traditional control methods based on copper compounds and antibiotics have resulted in the development of resistance in the bacterial population. Thus, alternative approaches are needed, such as phage therapy. This study aimed to characterize the physicochemical and biological properties of novel Pseudomonas syringae pv. syringae (Pss)-specific phages isolated from the soils of northwestern Iran. Seventy-five phage isolates were obtained, and their host range was determined against various bacterial pathogens. Five phages exhibiting the highest lytic activity against Pss and a narrow host range were selected for subsequent analysis. The stability of the selected phages was assessed under different conditions such as ultraviolet irradiation, temperature, pH, NaCl concentration, and chloroform exposure. The selected phages demonstrated significant effectiveness invivo, exerting substantial suppression on the population of Pss. This reduction was observed for both individual phages and when the phages were utilized as a mixture. The findings indicate that phages have the potential to be used as biocontrol agents in agriculture.

Chloroform associated with bone mineral density and bone mineral content in adults: A population-based cross-sectional research.

Bone mineral density is an important indicator of osteoporosis, and its variation with volatile organic compounds exposure has rarely been studied. However, the relationship between chloroform (an essential volatile organic compounds component) and bone mineral density remains unclear. Consequently, we aimed to explore the relationship between chloroform alone and bone mineral density or bone mineral content. Herein, 2,553 individuals aged 18 and above from the National Health and Nutrition Examination Surveys (NHANES) in 2009-2010, 2013-2014, and 2017-2020, were included. We employed two independent t-tests and multi-linear regression models to statistically assess the relationship between chloroform exposure and BMD/BMC in the spine and femoral area. A "V"-shaped correlation between chloroform exposure and bone mineral density or bone mineral content (BMD/BMC) was observed in the unadjusted model, particularly in the Ward's triangle and femoral neck as a whole. A negative correlation was specifically observed for the Ward's triangle BMD/BMC and L4 BMD/BMC. On the other hand, in the adjusted model, a dominantly negative correlation between the L4 BMC and chloroform exposure was observed over a range of exposure levels. The subgroup analysis revealed a negative correlation between chloroform concentrations and BMC in the femur and spine, especially in women and the 65-80 age population. Our study revealed a "V" shaped correlation between chloroform and BMD/BMC of the femur and spine in U.S. adults. This finding highlights the fact that prolonged exposure to chloroform may cause the changes in BMD/BMC.

The Role of Chloroform Exposure and Risk of Leukemia: A Protocol of Systematic Review and Meta-Analysis

Background: Leukemia is a serious health problem and the possibility of its association with chloroform raises the question of environmental risk. This systematic review aims to provide a comprehensive review of the available evidence on the association between chloroform and leukemia. Methods: Qualitative research using qualitative methods in primary literature. Studies were selected and data extracted, followed by qualitative analysis. Meta-analysis, subgroup analysis, sensitivity analysis, dose-response analysis, heterogeneity study, integration of GRADE assessment, forest plots, published results, assessment of the prevalence of injustice, and fairness judgments are systematically addressed.Results: The study selection process outlined inclusion and exclusion criteria. Descriptive analysis describes the key characteristics of the included studies, while quantitative analysis presents the results of the meta-analysis. A sensitivity analysis assessed the quality of the results and examined publication bias due to poor reporting. Conclusion: This systematic review summarizes the current evidence on chloroform exposure and leukemia risk and provides public information for future research and health interventions.

Cytotoxicity and genotoxicity evaluation of chloroform using Vicia faba roots.

Chloroform is a widely used industrial chemical that can also pollute the environment. The aims of this study were to examine the potential cytotoxicity and genotoxicity of chloroform on plant cells, using the Vicia faba bioassay. Chloroform was evaluated at concentrations of 0.1, 0.5, 1, 2, and 5mg·L-1. The following parameters were analyzed: the mitotic index (MI), micronucleus (MN) frequency, chromosomal aberration (CA) frequency, and malondialdehyde (MDA) content. The results showed that exposure to increasing concentrations of chloroform caused a decrease in MI and an increase in the frequency of MN in Vicia faba root tip cells, relative to their controls. Moreover, various types of CA, including C-mitosis, fragments, bridges, laggard chromosomes, and multipolar mitosis, were observed in the treated cells. The frequency of MN was positively correlated with the frequency of CA in exposure to 0.1-1mg·L-1 chloroform. Furthermore, chloroform exposure induced membrane lipid peroxidation damage in the Vicia faba radicle, and a linear correlation was observed between the MDA content and the frequency of MN or CA. These findings indicated that chloroform exposure can result in oxidative stress, cytotoxicity, and genotoxicity in plant cells.

Chloroform exposure in air and water in Swedish indoor swimming pools-urine as a biomarker of occupational exposure.

Disinfection by-products are produced in water disinfected with chlorine-based products. One such group is trihalomethanes, and chloroform is the most abundant trihalomethane in swimming pool areas. Chloroform can be absorbed by inhalation, ingestion, and dermal absorption, and is classified as possibly carcinogenic. To investigate if chloroform concentrations in air and water affect the chloroform concentration in urine samples of exposed swimming pool workers. Workers from 5 adventure indoor swimming pools carried personal chloroform air samplers and provided up to 4 urine samples during one workday. Chloroform concentrations were analyzed with a linear mixed model analysis to investigate a possible correlation between air and urine concentrations. The geometric mean chloroform concentration was 11 μg/m3 in air and 0.009 µg/g creatinine in urine among individuals with ≤2 h at work, 0.023 µg/g creatinine among those with >2-5 working hours, and 0.026 µg/g creatinine in the group with >5-10 working hours. A risk of higher levels of chloroform in urine was associated with longer hours at work (≤2 h versus >5-10 h, odds ratio [OR] 2.04, 95% confidence interval [CI] 1.25-3.34), personal chloroform concentrations in air (≤17.00 µg/m3 versus >28.00 µg/m3, OR 9.23, 95% CI 3.68-23.13) and working at least half the working day near the swimming pools (OR 3.16, 95% CI 1.33-7.55). Executing work tasks in the swimming pool water was not associated with higher chloroform concentrations in urine compared to only working on land (OR 0.82, 95% CI 0.27-2.45). There is an accumulation of chloroform concentrations in urine during a workday and a correlation between personal air and urine concentrations of chloroform among workers in Swedish indoor swimming pools.

Sensitive and Selective Detection of Chloroform by Current-Voltage Using ZnO Nanorods Modified Electrode

The development of in situ chloroform detection is crucial due to the high risk of carcinogenic effects associated with chloroform exposure. In this study, an electrochemical-based chloroform sensor was fabricated using undoped ZnO nanorods on indium tin oxide (ZnONRs/ITO) electrode to detect chloroform in aqueous-phase samples. Based on the results, the FESEM imaging showed that the ZnONRs exhibited an evenly distributed circular structure with a diameter of 62-90 nm, while the EDX and XRD findings confirmed the presence of Zn and O elements deposited on the electrode surface. Furthermore, the phosphate buffer solution (PBS) solution significantly affected the performance of the modified electrode with an optimal concentration and pH of 0.1 M and pH 7. The results also highlighted the vital function of the modified ZnONRs/ITO electrode as an efficient electron mediator and its catalytic potential to induce chloroform oxidation. Most importantly, the modified ZnONRs/ITO electrode was able to detect the presence of chloroform in real seawater samples, where the repeatability and reproducibility tests achieved a Relative Standard Deviation (RSD) of 1.41% and 2.61%, respectively, indicating the exceptional performance of the modified electrode. Moreover, the modified ZnONRs/ITO electrode recorded a low limit of detection and high sensitivity of 1.50 µM and 2.11 µA/cm2·mM, respectively, within a 0.010-10 mM linear dynamic range. In conclusion, the current-voltage (I-V) method proved the reliable, satisfactory, and effective fabrication of the modified ZnONRs/ITO electrode for chloroform sensing in aqueous-phase samples, including in real seawater samples.

VERY COMPLEX KARYOTYPE IN YOUNG MYELODYSPLASTIC SYNDROME PATIENT AFTER CHRONIC EXPOSURE TO CHLOROFORM

Myelodysplastic Syndrome (MDS) is marked by biological and clinical heterogeneity, characterized by dysplasia in the bone marrow and blood cells with the presence of cytopenias. MDS is recognized as a disease in elderly individuals. About 86% of MDS cases are diagnosed at age ≥ 60 and less than 10% of patients are younger than 50. Recurrent cytogenetic abnormalities are present in 40% to 60% of cases. Cytogenetic analysis plays an important role, whether in the diagnosis or classification of the disease. Recently, the new international molecular prognostic score system (IPSS-M) reinforces the valuable prognostic contribution of cytogenetics in MDS in both survival and leukemic evolution. To report a chronic chloroform exposure as a trigger capable of inducing DNA damage. Chronic exposure to a genotoxic agent has been linked to MDS chromosomal abnormality. Among these, chloroform, and an inorganic halide derivative of hydrocarbons can induce the DNA lesion. A 24-year-old male patient with a marked history of 10-year chloroform exposure sought medical attention for anemia, fainting, and unintentional weight loss. He was diagnosed with Myelodysplastic Syndrome and refractory anemia with excess blasts (RAEB II) with initial tests: Hb = 5 g/dL; neutrophils=320/mm3; platelets= 18 x 109/L. Bone marrow aspiration showed 15% myeloblasts, immunohistochemistry profile showed CD34+, CD117+ in blasts and cytogenetic analysis showed a very complex karyotype: 45,XY,del(6)(q22),-7,add(9) (q12),del(12)(p11.2),del(17)(p13),del(20)(q12),add(21(p13)[17]/46, XY[3]. Chemotherapy with azacitidine was performed as a bridge to bone marrow transplantation, but the patient evolved into sepsis, dying eight months after diagnosis. The pathogenesis of MDS reflects the heterogeneity of the disease, thus, comprises multiple steps and includes factors that can be endogenous and/or exogenous. Therefore, this unusual case shows the extreme importance of investigating possible recurrent and/or occupational exposures in these patients combined with cytogenetics analyses.

Assessing volatile organic compounds exposure and prostate-specific antigen: National Health and Nutrition Examination Survey, 2001-2010.

BackgroundVolatile organic compounds (VOCs) are a large group of chemicals widely used in people's daily routines. Increasing evidence revealed the VOCs' accumulating toxicity. However, the VOCs toxicity in male prostate has not been reported previously. Thus, we comprehensively evaluated the association between VOCs and prostate-specific antigen (PSA).MethodsA total of 2016 subjects were included in our study from the National Health and Nutrition Examination Survey with VOCs, PSA, and other variables among U.S. average population. We constructed XGBoost Algorithm Model, Regression Model, and Generalized linear Model (GAM) to analyze the potential association. Stratified analysis was used to identify high-risk populations.ResultsXGBoost Algorithm model identified blood chloroform as the most critical variable in the PSA concentration. Regression analysis suggested that blood chloroform was a positive association with PSA, which showed that environmental chloroform exposure is an independent risk factor that may cause prostate gland changes [β, (95% CI), P = 0.007, (0.003, 0.011), 0.00019]. GAM observed the linear relationship between blood chloroform and PSA concentration. Meanwhile, blood chloroform linear correlated with water chloroform in the lower dose range, indicating that the absorption of water may be the primary origin of chloroform. Stratified associations analysis identified the high-risk group on the chloroform exposures.ConclusionThis study revealed that blood chloroform was positively and independently associated with total PSA level, suggesting that long-term environmental chloroform exposure may cause changes in the prostate gland.

Exposure to Chloramine and Chloroform in Tap Water and Adverse Perinatal Outcomes in Shanghai.

Chloramine and chloroform are widespread in tap water due to water disinfection processes. This study was designed to explore the associations between trimester-specific exposure to chloramine and chloroform in tap water and adverse outcomes. This retrospective cohort study included 109,182 mother–infant singleton pairs in Shanghai. A logistic regression model was used to evaluate the associations of chloramine and chloroform concentrations averaged over the whole pregnancy and in each trimester with adverse outcomes, including gestational diabetes mellitus (GDM), gestational hypertensive disorders (GHD), low birthweight (LBW), small for gestational age (SGA), preterm birth (PTB) and prelabor rupture of membranes (PROM). The use of tap water with elevated chloramine levels in the first trimester was associated with GDM (OR = 1.06, 95% CI: 1.03, 1.09), while that in the second trimester was related to GHD (OR = 1.13, 95% CI: 1.09, 1.17). Chloroform levels in the third trimester were associated with LBW (OR = 1.13, 95% CI: 1.09, 1.16), PTB (OR = 1.05, 95% CI: 1.01, 1.08) and PROM (OR = 1.01, 95% CI: 1.00, 1.01). However, tap water chloroform exposure in the second trimester was negatively associated with LBW (OR = 0.95, 95% CI: 0.93, 0.98) and PTB (OR = 0.97, 95% CI: 0.94, 0.99). In conclusion, there are probably no casual associations between current tap water chloroform and chloramine levels and perinatal outcomes. However, more research focusing on the effect of chloramine and chloroform on perinatal outcomes are still warranted.

Mass mortality of pearl oyster (Pinctada fucata (Gould)) in Japan in 2019 and 2020 is caused by an unidentified infectious agent.

Mass mortality of 0-year-old pearl oysters, Pinctada fucata (Gould), and anomalies in adults were observed in Japan’s major pearl farming areas in the summer of 2019 and 2020. Although adult oyster mortality was low, both adult and juvenile oysters underwent atrophy of the soft body, detachment of the mantle from nacre (the shiny inner surface of the valves), deposition of brownish material on the nacre, and loss of nacre luster. Infection trials were conducted to verify the involvement of pathogens in this phenomenon. Healthy adult pearl oysters were obtained from areas where this disease had not occurred to use as the recipients. The sources of infection were either affected adult oysters with atrophied soft bodies or batches of juveniles in which mortality had reached conspicuous levels. Transmission of the disease to the healthy oysters were tested either by cohabitation with affected oysters or by injections of the hemolymph of affected animals. The injection infection test examined the effects of filtration and chloroform exposure on the pathogen. Occurrence of the disease was confirmed by the appearance of brown deposits on the nacre and loss of nacre luster. The abnormalities of nacre were clearly reproduced in recipient shells in three out of four cohabitation trials with affected oysters. The disease was also reproduced in six out of six injection trails either with hemolymph filtered through 100 nm filter or with hemolymph treated with chloroform. In a serial passage with hemolymph injections, the disease was successfully transmitted through eight passages. These results suggest that the etiology of the disease is a non-enveloped virus with a diameter ≤100 nm.

A Chemist with a Strange Etiology of Rhabdomyolysis: A Case Report of a Rare Toxicological Emergency.

IntroductionChloroform, a halogenated hydrocarbon, causes central nervous depression, hepatotoxicity, nephrotoxicity, and rhabdomyolysis. Historically, chloroform had been used as a general anaesthetic and today is still used in chemical industries. Lack of proper personal protective equipment and adequate knowledge about its toxic effects can lead to serious harm.Case reportA 33-year-old gentleman presented to the emergency department (ED) with altered mental status. Given his depressed mental status, the decision was made to intubate shortly after arrival for airway protection. Further history raised suspicion of occupational chloroform exposure. Brown-colored urine further strengthened suspicion of chloroform poisoning with resultant rhabdomyolysis. Forced alkaline diuresis and N-acetylcysteine were started in the ED. His mental status and respiratory efforts improved on hospital day two, and he was ultimately extubated. Creatine phosphokinase and myoglobin levels were initially high but gradually came down by hospital day six. On hospital day 10, the patient was deemed stable and safely discharged.ConclusionA patient with chloroform inhalation who suffered resultant rhabdomyolysis and hepatotoxicity was successfully treated with early initiation of forced alkaline diuresis, N-acetylysteine, and hemodialysis.

Effect of chloroform on the cyclic fatigue resistance of nickel-titanium retreatment instruments

Background: The purpose of this study was to evaluate the cyclic fatigue resistance of 4 different rotary nickel-titanium (NiTi) retreatment instruments after immersion in chloroform solution. Methods: A total of 120 ProTaper D3, R-Endo R3, D-Race DR2 and Mtwo R2 retreatment instruments were used. Thirty instruments of each system were randomly divided into 2 groups (n=15); Group 1: no immersion and Group 2: immersion in chloroform for 5 min. The instruments were operated in a dynamic cyclic fatigue test device until fracture occurred. The number of cycles to fracture and length of the fractured fragment for each instrument were recorded. Representative samples were examined under a scanning electron microscope. Data were analyzed by using 2-way analysis of variance and Bonferroni tests. Results: The ProTaper D3 and R-Endo R3 instruments showed the highest cyclic fatigue resistance whether or not immersed in chloroform (p<0.05). The immersion in chloroform did not affect the cyclic fatigue resistance of the instruments (p>0.05). The Mtwo R2 instruments were more resistant to cyclic fatigue than the D-Race DR2 instruments before and after immersed in chloroform (p<0.05).Conclusion: The immersion in chloroform had no effect on the cyclic fatigue resistance of retreatment instruments. The ProTaper D3 and R-Endo R3 instruments were more resistant to cyclic fatigue than other retreatment instruments regardless of chloroform exposure. Keywords: chloroform, cyclic fatigue, endodontics, nickel-titanium, retreatment

Approaches to Regulating Organic Carbon and the Necessity of Its Obligatory Monitoring in Drinking Water

Background: Current accumulation of organogenic elements in surface waters is mainly attributed to intensive anthropogenic activities. Waterborne organic matter may endanger human health when using surface waters for drinking and recreational purposes. Applied techniques of water treatment fail to ensure complete water purification and part of organic substances (their low molecular weight fraction) still remains. Chlorination of drinking water can generate a variety of halogenated by-products having adverse health effects in humans including carcinogenic ones. Our objective was to substantiate the reference value for total organic carbon (TOC) in water disinfected by chlorine. Materials and methods: We analyzed the results of laboratory testing of surface and treated water samples taken in Yekaterinburg in 2013–2014 and 2017, carried out health risk assessment, and built predicative models of by-products formation. Results: We established that, following chlorination, TOC concentrations became 1.5 times lower while chloroform and total trihalomethane concentrations became 24.5–80.2 and 22.9–54.5 times higher than initial values, respectively. The most significant non-carcinogenic risks were estimated for children aged 0-6 years from exposures to chloroform (HQ = 1.150). Individual carcinogenic risks from exposures to bromoform and dibromochloromethane as measured in water before its supplying to the distribution system, referred to the first value range (less than 1×10–6) while risks from bromodichloromethane and chloroform exposures fell in the second range (from 1×10–6 to 1×10–4). The mathematical model of the correlation between predictors (temperature, reaction time, pH, and certain chemical compounds) and levels of by-products was built. Conclusions: Our model makes it possible to predict generation of organochlorine compounds at the design stage of water treatment technique. Total organic carbon is an important indicator that should be monitored at the stages of water treatment to ensure safety of drinking water and efficiency of its disinfection.

Delayed onset of liver injury after intentional chloroform overdose: a case report and literature review

Chloroform is a recognised cause of acute liver injury, although now rarely encountered in clinical practice. We present a case of inhalational chloroform self-poisoning in a 47-year-old man that presented to hospital initially with reduced conscious level and later developed acute liver injury that was treated with intravenous acetylcysteine. This paper reviews the existing literature and presents a summary of the mechanisms of chloroform hepatotoxicity. Published cases show that there is a characteristic delay of 24 to 48 hours between chloroform exposure and elevation of liver transaminase activity. Therefore, clinicians need to provide an appropriate duration of monitoring in order to detect the occurrence of this important toxic effect.

Impact of chloroform exposures on reproductive and developmental outcomes: A systematic review of the scientific literature.

We assessed the animal and epidemiological data to determine if chloroform exposure causes developmental and/or reproductive toxicity. Initial scoping identified developmental toxicity as the primary area of concern. At levels producing maternal toxicity in rats and mice, chloroform caused decrements in fetal weights and associated delays in ossification. In a single mouse inhalation study, exposure to a high concentration of chloroform was associated with small fetuses and increased cleft palate. However, oral exposure of mice to chloroform at a dose 4 times higher was negative for cleft palate; multiple inhalation studies in rats were also negative. Epidemiologic data on low birth weight and small for gestational age were generally equivocal, preventing conclusions from being drawn for humans. The animal data also show evidence of very early (peri-implantation) total litter losses at very high exposure levels. This effect is likely maternally mediated rather than a direct effect on the offspring. Finally, the epidemiologic data indicate a possible association of higher chloroform exposure with lower risk of preterm birth (<37 weeks gestation). The available animal data suggest that exposures lower than those causing maternal toxicity should be without developmental effects in the offspring. Also, most studies in humans rely on group-level geographic exposure data, providing only weak epidemiologic evidence for an association with development outcomes and fail to establish a causal role for chloroform in the induction of adverse developmental outcomes at environmentally relevant concentrations.

Chloroethene. Documentation of proposed values of occupational exposure limits (OELs)

Chloroethene. Documentation of proposed values of occupational exposure limits (OELs)