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At least 19 recordsLinked to original sources

[The application of transgenic plant in evaluating the genotoxicity of environmental contaminants].

Environmental contaminants are powerful mutagenic factors for organisms. Several testing materials and methods have been used to assess the genotoxicity of environmental factors. Transgenic plants testing system can not only evaluate the level of genotoxicity, but also provide information on the genetic effects at molecular level. We introduce the use of transgenic plants in biomonitoring environmental factors.

Animals↗

High on pollution: drugs as environmental contaminants.

Environmental protection has advanced in leaps and bounds over recent years and today we undoubtedly live in a much cleaner world than we did a generation ago. But look closely and all is not what it seems. Rather than reducing pollution, we are, in fact, still bathed in a sea of chemicals. What is more, most of them originate not from factories or agriculture but from our own homes, in the form of drugs and consumer products. Tackling these diffuse sources presents one of the main environmental challenges of the 21st century.

Cosmetics↗

[Polycyclic aromatic hydrocarbons. I. Environmental contamination and environmental exposure].

Polycyclic aromatic hydrocarbons (PAHs) represent danger ubiquitous environmental pollutants. A lot of them have toxic and carcinogenic potential. Presented work summarises most of available data describing properties, origin and occupational and non-occupational sources of PAHs. Contamination of environment is described separately for air, water, soil, sediments and food. Possibilities of occupational and non-occupational exposure of persons are discussed and populations with potentially high exposures to PAHs are defined. The work is concluded by digest of regulations and guidelines regarding environmental contamination of PAHs.

Environmental Pollutants↗

Environmental contamination due to methicillin-resistant Staphylococcus aureus: possible infection control implications.

OBJECTIVE: To study the possible role of contaminated environmental surfaces as a reservoir of methicillin-resistant Staphylococcus aureus (MRSA) in hospitals. DESIGN: A prospective culture survey of inanimate objects in the rooms of patients with MRSA. SETTING: A 200-bed university-affiliated teaching hospital. PATIENTS: Thirty-eight consecutive patients colonized or infected with MRSA. Patients represented endemic MRSA cases. RESULTS: Ninety-six (27%) of 350 surfaces sampled in the rooms of affected patients were contaminated with MRSA. When patients had MRSA in a wound or urine, 36% of surfaces were contaminated. In contrast, when MRSA was isolated from other body sites, only 6% of surfaces were contaminated (odds ratio, 8.8; 95% confidence interval, 3.7-25.5; P < .0001). Environmental contamination occurred in the rooms of 73% of infected patients and 69% of colonized patients. Frequently contaminated objects included the floor, bed linens, the patient's gown, overbed tables, and blood pressure cuffs. Sixty-five percent of nurses who had performed morning patient-care activities on patients with MRSA in a wound or urine contaminated their nursing uniforms or gowns with MRSA. Forty-two percent of personnel who had no direct contact with such patients, but had touched contaminated surfaces, contaminated their gloves with MRSA. CONCLUSIONS: We concluded that inanimate surfaces near affected patients commonly become contaminated with MRSA and that the frequency of contamination is affected by the body site at which patients are colonized or infected. That personnel may contaminate their gloves (or possibly their hands) by touching such surfaces suggests that contaminated environmental surfaces may serve as a reservoir of MRSA in hospitals.

Bacterial Typing Techniques↗

The psychological dimensions of health care for patients exposed to radiation and the other invisible environmental contaminants.

Invisible environmental contaminants are those contaminants that possess environmental and/or medical invisibility. Recent studies indicate: (1) that these contaminants can and do have traumatic psychological effects on those individuals who have been exposed to them and (2) that there is a remarkable uniformity to these traumatic affects as they have been found in the various invisible exposures that have been studied to date. The common denominators in all of these situations is the invisibility of the involved contaminants. The adverse psychological effects of the invisible contaminants are as follows: (1) experienced uncertainty, (2) adaptational dilemmas, (3) hypervigilance, (4) nonempirical belief systems about the exposure, and (5) traumatic neuroses. This paper will: (1) review the data that documents the occurrence of psychological effects of the invisible environmental contaminants, (2) present an adaptational model that explains the manner in which these psychological trauma develop, and (3) examine the clinical and public policy implications of these findings.

Environmental Pollutants↗

Alterations in steroidogenesis in alligators (Alligator mississippiensis) exposed naturally and experimentally to environmental contaminants.

Many environmental contaminants alter the reproduction of animals by altering the development and function of the endocrine system. The ability of environmental contaminants to alter the endocrine system of alligators was studied both in a descriptive study in which juvenile alligators from a historically contaminated lake were compared to animals from a control lake and in an experimental study in which hatchling control alligators were exposed in ovo to several endocrine-disrupting standards and two modern-use herbicides. Endocrine status was assessed by examining plasma hormone concentrations, gonadal-adrenal mesonephros (GAM) aromatase activity, and gonadal histopathology. In the descriptive study, juvenile alligators from the contaminated lake had significantly lower plasma testosterone concentrations (29.2 pg/ml compared to 51.3 pg/ml), whereas plasma 17 beta-estradiol concentrations did not vary when compared to controls. GAM aromatase activity was significantly decreased n the alligators from the contaminated lake (7.6 pmol/g/hr compared to 11.4 pmol/g/hr). In the experimental study, the endocrine-disrupting standards had the expected effects. 17 beta-Estradiol and tamoxifen caused sex reversal from male to female, with a corresponding increase in aromatase activity. Vinclozolin had no apparent effect on male or female alligators. Among the herbicides tested, atrazine induced GAM aromatase activity in male hatchling alligators that was neither characteristic of males nor females, although testicular differentiation was not altered. Exposure to 2,4-dichlorophenoxyacetic acid had no effect on the endocrine parameters that were measured. Together, these studies show that exposure to some environmental chemicals (such as atrazine) can alter steroidogenesis in alligators, but the endocrine alterations previously noted for Lake Apopka, Florida, alligators can not be fully explained by this mechanism.

Alligators and Crocodiles↗

Role of environmental contamination as a risk factor for acquisition of vancomycin-resistant enterococci in patients treated in a medical intensive care unit.

BACKGROUND: Colonization pressure, proximity to another case, exposure to a nurse who cares for another case, enteral feeding, and the use of sucralfate, vancomycin hydrochloride, cephalosporins, or antibiotics are among the defined risk factors for acquisition of vancomycin-resistant enterococci (VRE) in the intensive care unit (ICU) setting. However, the role of rooms with contaminated environmental surfaces has not been well delineated. METHODS: Retrospective case-control study conducted on patients admitted to the medical ICU (MICU) of a tertiary-care, university-affiliated medical center during a 9-month period. Patients who acquired VRE (cases) were matched with 2 randomly selected control subjects who did not acquire VRE and had been in the MICU for at least the same number of days. RESULTS: Thirty cases were matched with 60 appropriate controls. Cases were more likely to have been in the hospital for longer than 7 days before MICU admission (P =.009); to have occupied a specific room with persisting contaminated surfaces (P =.06); to have had a central venous catheter (P =.05); to have received vancomycin (P =.02), cephalosporins (P =.03), and quinolones (P =.006) before MICU admission; and to have received vancomycin (P =.02) and metronidazole sodium phosphate (P =.03) after MICU admission. Multivariate analysis showed that a hospital stay of longer than 1 week before MICU admission (P =.04), use of vancomycin before or after MICU admission (P =.03), use of quinolones before MICU admission (P =.03), and placement in a contaminated room (P =.02) were the best predictors of VRE acquisition. CONCLUSIONS: Among all other factors associated with VRE transmission, VRE acquisition may depend on room contamination, even after extensive cleaning. This study underscores the need for better cleaning and the role of the environment in transmission of VRE.

Aged↗

[Environmental contamination and children].

Environmental contamination is a growing problem and a major worldwide concern. Industrialization and overpopulation underlie it's first origins. Contamination has severe outcomes for the whole planet, and very particularly for mankind. But these consequences are specially ominous for childhood. Childs are more extensively exposed to contaminants than adults, for a longer period of time, and the effects are more deleterious as they act during the period of growth and development Concerning the risks associated to contaminants there is still a large paucity of data, particularly as referred to low grade exposure.

Abnormalities, Drug-Induced↗

Environmental contaminants in human milk.

Environmental contaminants can be stored in the mother's body or can be transiently present from current diet, occupational exposures or personal habits. These chemicals can be transferred prenatally to the developing fetus or postnatally from breast milk to the nursing infant. Exposures through breast milk can be substantial, especially when the mother has significant ongoing exposures or has accumulated an unusually high body burden of persistent chemicals. Several studies demonstrate that organochlorines (OCs) acquired from breast milk elevate a child's body burden for several years. The decline of persistent OC residues in Western countries suggests that these exposures through breast milk will also diminish. Heavy metals such as lead and mercury are also present in milk, but the pharmacokinetics are quite different from OCs. Less persistent environmental agents, including solvents, polycyclic aromatic hydrocarbons, certain pesticides, and nicotine, can also be detected in milk. There is little information on currently used pesticides and other more recently identified environmental agents for which exposures are common today. Epidemiologic research has established that pre- and postnatal exposures to environmental contaminants including lead and OCs are associated with developmental deficits in early childhood. Therefore, characterization of these contaminants in breast milk can add to our knowledge of potential environmental exposures among children.

Adult↗

Pet dogs as sentinels for environmental contamination.

The presence of environmental contaminants in air, water and food may pose significant health risks to the exposed human population. However, problems associated with assessing chronic exposure to low doses of environmental chemicals, multiple exposure routes, diseases with long latency periods, and non-specific health outcomes make it difficult to conduct the appropriate human epidemiologic studies. It may be useful to complement human epidemiology with animal studies. Animals monitored or evaluated in situ for the appropriate suite of endpoints can provide information about both exposure levels and potential adverse health effects. Animals have served as sentinel indicators for health effects associated with a number of environmental exposures, including pesticides and asbestos. Pet dogs may be particularly valuable sentinels because they share the human environment. In addition, dogs respond to many toxic insults in ways analogous to humans, they have physiologically compressed life spans, and they are free from some important lifestyle risk factors for disease. An example of how pet dogs may be used as sentinels for potential human health hazards involves a study of the genotoxic effects resulting from exposure to a mixture of chemicals from nearby Superfund sites. We conducted a cross-sectional study of exposed dogs (living in the community with the Superfund sites) and controls (living in a nearby community). The pet owners completed a questionnaire, and we collected a blood sample from each dog. The blood samples were analyzed for standard clinical parameters and assays for possible genotoxic effects (peripheral blood lymphocyte micronucleus frequency and lymphocyte subtyping). Pet dogs living near the Superfund sites had a higher micronucleus frequency than control animals, suggesting that the dogs may have been exposed to environmental contaminants from these sites.

Alanine Transaminase↗

[The preparation of the surgical team: significant aspect in the control of environmental contamination].

The control of environmental contamination has been considered a rational measure for preventing surgical site infection. This study aims to present the current recommendations related to the preparation of the surgical team and to discuss the role of nurses in controlling environmental contamination. On the basis of current literature, we treat issues related to surgical garment and hand brushing. Studies indicate that the preparation of the surgical team constitutes an important protection barrier for preventing surgical site infection; nevertheless, the need is highlighted for health professionals to realize procedures adequately.

Environmental Pollution↗

Some scientific judgments in the assessment of the risk of environmental contaminants.

The assessment of risk due to environmental contaminants depends, in part, on scientific data. When such data are incomplete, as is usually the case, assumptions based on scientific judgments are made to analyze the consequences. Specifically, when health related data needed to assess the risk posed by environmental contaminants are missing or incomplete, it becomes necessary to make assumptions using scientific judgment to estimate the risk. Different scientists can and do make different assumptions, and the resulting differences in opinion can result in controversy. The present discussion presents a few of the consensus judgments of the Science Advisory Board (SAB) of the U.S. Environmental Protection Agency concerning the health effects and risk for such environmental contaminants as 1,2-dichloroethylene, dichloromethane, para-dichlorobenzene, polychlorinated biphenyls, perchloroethylene, and xylene, as well as the implications of the more likely cancer mechanisms, the exposure routes, and pharmacokinetics to the risk assessment process. In some of these examples, the scientific data have been developed to the extent that specific judgments by groups such as the SAB can result in greater confidence that one is correct in the assessment of risk. Because of the uncertainties in current scientific knowledge for many environmental contaminants, judgments differ and there is no right or wrong opinion.

Animals↗

Environmental contaminants in breast milk.

Toxic environmental contaminants can be transferred from mother to infant via breastfeeding. Persistent organic pollutants (POPs) are a family of lipophilic stable chemicals that bioaccumulate in adipose tissue and create a lasting toxic body burden. Breastfeeding provides a significant source of exposure to POPs early in human life, the effects of which are unknown, and is the subject of a growing body of research. Despite the possibility of harm from environmental contaminants in breast milk, breastfeeding is still recommended as the best infant feeding method. This article reviews what is known about POPs in breast milk and their effect on infant development to inform clinicians about the issue, provide recommendations for practice, and promote environmental and public health policies that reduce human exposure to harmful pollutants.

Body Burden↗

Do environmental contaminants adversely affect human reproductive physiology?

There is increasing concern among Canadian women that unwitting and unwanted exposures to environmental contaminants are adversely affecting their health, particularly their ability to become pregnant and have a healthy baby. Evidence of adverse reproductive outcomes among populations exposed to environmental contaminants in the workplace via accidental poisoning, together with detection of environmental contaminant residues in serum and ovarian follicular fluid, has led to the hypothesis that chemical contaminants may be contributing to adverse reproductive outcomes such as infertility, endometriosis, polycystic ovary syndrome, spontaneous abortion, preterm labour, intrauterine growth restriction, and pregnancy-induced hypertension in the general population. The lack of clear evidence concerning the association between exposure to environmental contaminants and adverse reproductive outcomes hampers the clinician's ability to counsel women who are trying to conceive or who have concerns about their pregnancy. This review summarizes the evidence linking environmental contaminant exposure to selected adverse health outcomes by examining the changes in health-outcome trends, the consistency of the epidemiological evidence of an association between the health outcome of concern and exposure to environmental contaminants, and the biological plausibility for environmental contaminant mediated effects on human reproductive health. At best, only a moderate association can be found linking exposure to environmental contaminants with evidence of deleterious reproductive effects in women. Lack of disease trend data, weak exposure assessments, and limited mechanistic data supporting the biological plausibility of potential effects are the primary limitations to the hypothesis that exposure to environmental contaminants adversely affects human reproductive physiology.

Animals↗

An improved mouth-piece to prevent environmental contamination during radioaerosol inhalation procedures.

The literature suggests that environmental contamination is common during labeled aerosol inhalation procedures in nuclear medicine. We have tested an adherent mask to prevent environmental contamination in 70 procedures. Two groups of patients were evaluated. Group 1 (60 inhalation cases in which the mask was used) presented no environmental contamination in 95% of the procedures (means of 553 dpm and 596 dpm before and after inhalation, p > 0.05, mean of the differences before/after inhalation 6.95, SD = 21.2 dpm) and the only 3 cases in which contamination did occur concerned bearded men; Group 2 (10 inhalation cases in which the mask was not used) showed large increases of environmental radioactive levels in 70% of the procedures (means of 601 dpm and 2,756 dpm before and after inhalation, p < 0.05, mean of the differences 3,066, SD = 2,98 dpm). We conclude that such a mask is very helpful in avoiding environmental contamination during radioaerosol inhalation procedures.

Administration, Inhalation↗

Development of local knowledge of environmental contamination in Sydney, Nova Scotia: environmental health practice from an environmental justice perspective.

In Sydney, Nova Scotia, from 1901 through 1988 a coke and steel factory operated with no pollution controls, depositing over a million tons of particulate matter and releasing several thousands of tons of coal tar into the estuary. Previously we documented the presence of lead, arsenic and PAHs, in soil above Canadian guidelines, and in house dust in the communities surrounding the site [Lambert, TW, Lane, S. Lead, arsenic, and polycyclic aromatic hydrocarbons in soil and house dust in the communities surrounding the Sydney, Nova Scotia, tar ponds. Environ Health Perspect 2004; 112:35-41.]. In this paper we further the research by documenting and developing community knowledge with a study of resident's observations and experiences of the industrial contamination. We conducted two surveys, a quantitative door-to-door survey and qualitative dust interview, designed to complement each other and bring together the observations and experiences in the different communities to develop the local knowledge. The combined methodology uses techniques from both social and physical science, and was developed with the cooperation of community members. The research supports the proposition that local knowledge adds contextual meaning that complements the physical measurement of environmental contaminants, in order to understand the complex environment in which people live, and the multiple exposure pathways through which they can be affected. Residents in all three communities provided vivid observations and detailed experiences of the industrial pollution in their community and homes. The local knowledge is consistent with our physical data and review of the historical scientific research in Sydney, and supports the inference that the community was adversely impacted by the coke and steel facility. From a justice perspective, the three communities should be equally considered for remediation as part of the 'tar pond remediation policy' rather than the current policy of including only a few streets and houses.

Air Pollution, Indoor↗

Approaches to detecting immunotoxic effects of environmental contaminants in humans.

Experimental animal studies indicate that environmental contaminants can have adverse effects on several organs and tissues of the immune system. Such effects are known to lead to increased host susceptibility to microbial infections and to compromised immunosurveillance mechanisms normally instrumental in the elimination of neoplastic cells and the prevention of autoimmune diseases. Evaluation of the potential risk environmental contaminants pose to the human immune system is currently accomplished via extrapolation of experimentally derived animal data to humans. Presently, this process requires that uncertainty factors such as interspecies differences and genetic variability be considered. Naturally, the process of risk assessment would be greatly facilitated if it were based on clinically relevant data derived from studying humans known to be exposed to environmental contaminants. However, the existing human data are scarce and often described as very limited in scope. To generate the much-needed human data we need to identify a set of clinically relevant immunologic end points that, when adequately standardized, can be incorporated easily into the design of prospective epidemiologic studies.

Biomarkers↗