Health Effects Of Environmental Chemicals Research Articles

Research on Health Effects of Environmental Chemicals Based on Structure and Gene Association Analysis

<p>China is a major producer and consumer of chemicals. The production and use of chemicals play a role in the development of the entire national economy. Therefore, effective chemical management has a huge impact on the development of the national economy. At present, chemical management guidelines have achieved a lot in chemical operations, but there are still many shortcomings. Relevant institutions should further improve the standard system, strengthen the coordination of subjective institutions, the supervision and management, establish information standards, complete information sharing, build a feedback system, strengthen the transformation of experimental results and trust training.</p>

Statistical Approaches to Address Multi-Pollutant Mixtures and Multiple Exposures: the State of the Science.

The purpose of this review is to describe the most recent statistical approaches to estimate the effect of multi-pollutant mixtures or multiple correlated exposures on human health. The health effects of environmental chemicals or air pollutants have been widely described. Often, there exists a complex mixture of different substances, potentially highly correlated with each other and with other (environmental) stressors. Single-exposure approaches do not allow disentangling effects of individual factors and fail to detect potential interactions between exposures. In the last years, sophisticated methods have been developed to investigate the joint or independent health effects of multi-pollutant mixtures or multiple environmental exposures. A classification of the most recent methods is proposed. A non-technical description of each method is provided, together with epidemiological applications and operational details for implementation with standard software.

Integrating human, animal, and mechanistic data to support hazard conclusions in a systematic review of health effects of environmental chemicals

Integrating human, animal, and mechanistic data to support hazard conclusions in a systematic review of health effects of environmental chemicals

Maternal Transfer of Bisphenol A During Nursing Causes Sperm Impairment in Male Offspring

The health effects of environmental chemicals on animals and humans are of growing concern. Human epidemiological and animal study data indicate that reproductive disorders and diseases begin early during prenatal and postnatal development. An increase of human male reproductive disturbance in the past several decades was associated to chemicals called endocrine disruptors (ED). Bisphenol A (BPA) is a ubiquitous organic environmental contaminant with ED activity. This study verified the effect of BPA exposure via breast milk during the lactation (early postnatal) period in male mice. Dams were exposed to oral BPA (300, 900, and 3000 µg/kg/BW/day) during the breastfeeding period (21 days). BPA at all concentrations significantly impaired sperm parameters in adult mice (8 months old), but mitochondrial functionality was more affected at BPA 3000. The acrosome membrane parameter was affected by BPA concentrations from 900 to 3000, and DNA integrity showed pronounced impairment at BPA 900 and 3000. BPA 3000 treatment also induced testicular degeneration and complete aplasia in some seminiferous tubules. Testicular oxidative damage was observed, and the total antioxidant capacity was impaired in BPA 900 and 3000 treatment groups. Taken together, the present study demonstrated long-term adverse effects of BPA in male mice, including reduced sperm quality, antioxidant capacity, and changes in testicular tissue. Our results clearly demonstrate the danger of BPA transferred via lactation on sperm quality registered even after a long time-elapsed from exposure to this harmful chemical.

Effects of Exposure to Environmental Chemicals During Pregnancy on the Development of the Male and Female Reproductive Axes

There is a large body of literature describing effects of environmental chemicals (ECs), many of them anthropogenic with endocrine-disrupting properties, on development in rodent laboratory species, some of which lead to impaired reproduction and adverse health. This literature joins extensive human epidemiological data and opportunistic wildlife findings on health effects of ECs. In contrast, the effect of endocrine disruption on foetal development and reproductive performance in domestic species is less extensively documented. This applies both to domestic farm and to companion species even though the former is critical to food production and the latter share our homes and many aspects of the modern developed human lifestyle. In domestic species, the nature of chemicals exposure in utero and their consequences for animal health and production are poorly understood. A complication in our understanding is that the pace of development, ontogeny and efficiency of foetal and maternal hepatic and placental activity differs between domestic species. In many ways, this reflects the difficulties in understanding human exposure and consequences of that exposure for the foetus and subsequent adult from epidemiological and largely rodent-based data. It is important that domestic species are included in research into endocrine disruption because of their (i) wide variety of exposure to such chemicals, (ii) greater similarity of many developmental processes to the human, (iii) economic importance and (iv) close similarities to developed world human lifestyle in companion species.

An overall risk probability-based method for quantification of synergistic and antagonistic effects in health risk assessment for mixtures: theoretical concepts

In the assessment of health risks of environmental pollutants, the method of dose addition and the method of independent action are used to assess mixture effects when no synergistic and/or antagonistic effects are present. Currently, no method exists to quantify synergistic and/or antagonistic effects for mixtures. The purpose of this paper is to develop the theoretical concepts of an overall risk probability (ORP)-based method to quantify the synergistic and antagonistic effects in health risk assessment for mixtures. The ORP for health effects of environmental chemicals was determined from the cumulative probabilities of exposure and effects. This method was used to calculate the ORP for independent mixtures and for mixtures with synergistic and antagonistic effects. For the independent mixtures, a mixture ORP can be calculated from the product of the ORPs of individual components. For systems of interacting mixtures, a synergistic coefficient and an antagonistic coefficient were defined respectively to quantify the ORPs of each individual component in the mixture. The component ORPs with synergistic and/or antagonistic effects were then used to calculate the total ORP for the mixture. An ORP-based method was developed to quantify synergistic and antagonistic effects in health risk assessment for mixtures. This represents a first method to generally quantify mixture effects of interacting toxicants.

Urine-sampling methods for environmental chemicals in infants and young children

This review paper examines and evaluates urine-sampling methodologies in infants and young children, to determine which methods are suitable for use in large biomonitoring surveys or studies of environmental chemicals in children younger than 6 years. Methods for non-toilet-trained children include the use of urine bags, collection pads (e.g., cotton or gauze inserts), disposable diapers, cotton diapers, and the clean catch method. In toilet-trained children, collection methods include use of a commode insert pan as well as specimen collection cups. The advantages and disadvantages of these various methods need to be evaluated with respect to the target population, timing and frequency of collection, minimum sample volume required, method of urine extraction, potential for contamination of the sample, stability of the analyte of interest, and burden on participants and research team. Collection methods must not introduce contamination or affect the integrity of the sample, should be logistically practical, and should minimize discomfort experienced by the child. Although collection of urine samples from children who are not toilet-trained is more challenging than collection from older toilet-trained children, the vulnerability of younger children to the exposure to and health effects of environmental chemicals makes finding suitable methods a priority.

Heavy Metal-induced Immunotoxicity and Its Mechanisms

Immunotoxic effects of heavy metals, as a typical environmental agent, and their mechanisms are reviewed based on our findings on autoimmune response induced by exposure to cadmium (Cd) as CdCl(2). Adverse immune effects of chemicals, defined as immunotoxicity, have been used as a sensitive biomarker for assessing health effects of environmental chemicals. My initial research focused on renal toxicity of heavy metals was developed to elucidate characteristics and mechanisms for immune-mediated nephritis induced by heavy metals. In our studies the most interesting finding was autoantibody production enhanced by the oral exposure to Cd at environmental levels. It was observed simultaneously with enhancement of non-specific antibody production and suppression of primed-antigen specific antibody production. Immunostimulation including induction of autoantibodies was found to be the primary immunotoxic effect of Cd, because of the dose-sensitivity, and to be associated with polyclonal B cell activation (PBA). Further mechanism studies on the PBA induced by Cd in vitro showed that it was mediated by T cells, via cytokines, dominantly Type-2 cytokines, and recognition of MHC-II antigens of cell surface. The similarity among PBAs induced by inorganic salts of Cd, mercury and lead suggests that it would be the common effect among the metals to be involved in their pathogenesis of nephritis. Finally possible health significance of chemical-induced PBA is discussed associated with an increasing trend of autoimmune diseases in industrialized countries.

Exploiting Gene‐Environment Interaction to Detect Adverse Health Effects of Environmental Chemicals on the Next Generation

There is increasing evidence from epidemiological studies that genetic susceptibilities may modify the teratogenic effects of toxic chemicals. However, in contrast to tobacco smoke, few epidemiological studies have addressed environmental chemicals, such as polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and polychlorinated biphenyls in regard to genetic susceptibility. Recent studies, including the Hokkaido Study of Environments and Children's Health, have investigated the impacts of both environmental and genetic factors on children's development. Several xenobiotic-metabolizing genes have been reported to confer genetic susceptibility to low birth weight. These genes seem to be influenced functionally by maternal smoking during pregnancy, itself a significant risk factor. In our study, we found that birth weight was significantly lower among infants born to smoking women having the specific AHR, CYP1A1, GSTM1, CYP2E1 and NQO1 genotypes. When combinations of these genotypes were considered, birth weight was even lower. On the other hand, congenital anomalies such as hypospadias seemed to be caused by environmental factors in conjunction with genetic predisposition as suggested by linkage in several case-control studies reported to low birth weight. We have found an association between maternal CYP1A1 genotype or low birth weight and the risk of hypospadias irrespective of smoking. At the same time, birth weight was negatively correlated with maternal blood concentrations of polychlorinated dibenzofurans. Further studies should elucidate the impact of genetic factors on adverse effects of exposures to dioxin-related chemicals.

Health Effects of Environmental Chemicals

"Polemical" is the best word to describe the voluminous literature about the health effects of environmental chemicals. The literature includes both lengthy scientific treatises that few read and brief emotional pleas heard by many; books that are one-sided representations and misdefinitions of important single words; and vitriolic attacks on subspecialities and people. Unfortunately, the literature does not include sufficient information to allow us to determine the risk posed by the majority of chemicals in the human environment. In light of this state of knowledge, planners must work with others to constrain potentially dangerous land uses.

Pollution: Causes, Effects and Control.

Chemical Pollution of the Aquatic Environment by Priority Pollutants and its Control Chemistry Pollution of the Marine Environment Drinking Water Quality and Health Water Pollution Biology Sewage and Sewage Sludge Treatment The Treatment of Toxic Wastes Air Pollution: Sources, Concentrations and Measurements Chemistry of the Troposphere Chemistry and Pollution of the Stratosphere Atmospheric Dispersal of Pollutants and the Modelling of Air Pollution The Health Effects of Air Pollution Impacts of Gaseous Pollutants on Crops, Trees and Ecosystems Control of Pollutant Emissions from Road Traffic Soil Pollution and Land Contamination Solid Waste Management Clean Technologies The Environmental Behaviour of Persistent Organic Pollutants Radioactivity in the Environment Health Effects of Environmental Chemicals The Legal Control of Pollution Integrated Pollution Control and Waste Minimisation Subject Index.

Pollution: Causes, effects and control

Chemical Pollution of the Aquatic Environment by Priority Pollutants and its Control Chemistry Pollution of the Marine Environment Drinking Water Quality and Health Water Pollution Biology Sewage and Sewage Sludge Treatment The Treatment of Toxic Wastes Air Pollution: Sources, Concentrations and Measurements Chemistry of the Troposphere Chemistry and Pollution of the Stratosphere Atmospheric Dispersal of Pollutants and the Modelling of Air Pollution The Health Effects of Air Pollution Impacts of Gaseous Pollutants on Crops, Trees and Ecosystems Control of Pollutant Emissions from Road Traffic Soil Pollution and Land Contamination Solid Waste Management Clean Technologies The Environmental Behaviour of Persistent Organic Pollutants Radioactivity in the Environment Health Effects of Environmental Chemicals The Legal Control of Pollution Integrated Pollution Control and Waste Minimisation Subject Index.