Water Quality for Grazing Livestock I

Water is the most important nutrient for rangeland livestock. However, competition with municipalities, industry, and other water users often results in grazing livestock being forced to use water supplies that are less than perfect. Surface water in western rangleands are often contaminated by mineral extraction, irrigation runoff and other human activities. Mineral contaminants in drinking water are additive with similar contaminants in feedstuffs. The goal of this and the subsequent article is to provide producers and veterinarians with the basic background to make informed decisions about whether a given water supply is "safe" for livestock.

Poisoning, Overdoses, Toxic Exposures

The national poison center movement originated in the Midwest with actions of the American Academy of Pediatrics in Chicago, Illinois, in 1972. The Missouri Poison Center (MPC) was established in 1974. The MPC and other regional poison centers are essential to the public health locally and nationally. Trends in serious poisoning outbreaks such as the release of synthetic cannabinoids have been detected by real-time electronic surveillance by specialists in poison information and medical toxicologists.

Data-Driven Method to Estimate Nonlinear Chemical Equivalence

There is great need to express the impacts of chemicals found in the environment in terms of effects from alternative chemicals of interest. Methods currently employed in fields such as life-cycle assessment, risk assessment, mixtures toxicology, and pharmacology rely mostly on heuristic arguments to justify the use of linear relationships in the construction of "equivalency factors," which aim to model these concentration-concentration correlations. However, the use of linear models, even at low concentrations, oversimplifies the nonlinear nature of the concentration-response curve, therefore introducing error into calculations involving these factors. We address this problem by reporting a method to determine a concentration-concentration relationship between two chemicals based on the full extent of experimentally derived concentration-response curves. Although this method can be easily generalized, we develop and illustrate it from the perspective of toxicology, in which we provide equations relating the sigmoid and non-monotone, or "biphasic," responses typical of the field. The resulting concentration-concentration relationships are manifestly nonlinear for nearly any chemical level, even at the very low concentrations common to environmental measurements. We demonstrate the method using real-world examples of toxicological data which may exhibit sigmoid and biphasic mortality curves. Finally, we use our models to calculate equivalency factors, and show that traditional results are recovered only when the concentration-response curves are "parallel," which has been noted before, but we make formal here by providing mathematical conditions on the validity of this approach.

Illegal Dumping of Toxic Waste and Its Effect on Human Health in Campania, Italy

The region of Campania (particularly Naples and Caserta) has experienced an emergency in the waste management cycle during past years. Although the most critical phase has been overcome after the construction of the incineration plant in Acerra (an old-fashioned technology built up over a few months, whose impact on environment and health has not yet been assessed), most of the underlying problems have not been resolved. The illegal burning of wheels, plastics, textiles, and other industrial residuals, along with the detection of two thousand toxic substance dumping sites, still represents major concerns of environmental pollution and population health. This review summarizes the most relevant studies, which analyzed chemical contamination (primarily dioxins and polychlorinated biphenyls (PCBs)) of the air, soil, water, animals, and humans in Campania. In addition, we reviewed information on population health (i.e., mortality data, congenital malformations, and cancer incidence). Moving from a detailed mapping of (mostly illegal) waste dumping sites in Campania, we have focused on recent studies which have found: (a) high concentrations of dioxins (≥5.0 pg TEQ/g fat) in milk samples from sheep, cows, and river buffaloes; (b) remarkable contamination of dioxin and PCBs in human milk samples from those living in the Naples and Caserta areas (PCDDs+PCDFs and dioxin-like-PCBs (dl-PCBs) assessed at 16.6 pg TEQ/g of fat; range: 7.5-43 pg/g of fat); (c) potential age-adjusted standardized mortality rates associated with some specific cancer types; (d) a statistically significant association between exposure to illegal toxic waste dumping sites and cancer mortality, even after adjustment by socio-economic factors and other environmental indicators.

Predicting chemically-induced skin reactions. Part II: QSAR models of skin permeability and the relationships between skin permeability and skin sensitization

Skin permeability is widely considered to be mechanistically implicated in chemically-induced skin sensitization. Although many chemicals have been identified as skin sensitizers, there have been very few reports analyzing the relationships between molecular structure and skin permeability of sensitizers and non-sensitizers. The goals of this study were to: (i) compile, curate, and integrate the largest publicly available dataset of chemicals studied for their skin permeability; (ii) develop and rigorously validate QSAR models to predict skin permeability; and (iii) explore the complex relationships between skin sensitization and skin permeability. Based on the largest publicly available dataset compiled in this study, we found no overall correlation between skin permeability and skin sensitization. In addition, cross-species correlation coefficient between human and rodent permeability data was found to be as low as R²=0.44. Human skin permeability models based on the random forest method have been developed and validated using OECD-compliant QSAR modeling workflow. Their external accuracy was high (Q²_ext = 0.73 for 63% of external compounds inside the applicability domain). The extended analysis using both experimentally-measured and QSAR-imputed data still confirmed the absence of any overall concordance between skin permeability and skin sensitization. This observation suggests that chemical modifications that affect skin permeability should not be presumed a priori to modulate the sensitization potential of chemicals. The models reported herein as well as those developed in the companion paper on skin sensitization suggest that it may be possible to rationally design compounds with the desired high skin permeability but low sensitization potential.

Poisoning in Israel: annual report of the Israel Poison Information Center, 2012

BACKGROUND

The Israel National Poison Information Center (IPIC), Rambam Health Care Campus, provides 24 hour telephone consultations in clinical toxicology as well as drug and teratogen information. It participates in research, teaching and regulatory activities, and also provides laboratory services.

OBJECTIVES

To report data on the epidemiology of poisonings and poison exposures in Israel.

METHODS

We made computerized queries and descriptive analyses of the medical records database of the IPIC during 2012.

RESULTS

A total of 31,519 poison exposure cases were recorded, a 157.6% increase compared with 1995. Children < 6 years of age were involved in 43.1% of cases; 74.0% of calls were made by the public and 23.7% by physicians; 74.8% of exposures were unintentional and 9.1% intentional. Chemicals were involved in 35.8% of all cases (single and multiple substances), pharmaceuticals in 48.8%, bites and stings in 3.8%, and plants and mushrooms in 1.6%. Substances most frequently involved were analgesics, cleaning products and antimicrobials. Clinical severity was moderate/major in 3.4%. Substances most frequently involved in moderate/major exposures were corrosives, insecticides and snake venom. Four fatalities were recorded; all were intentional exposures in adults (corrosive, medications, energy drink).

CONCLUSIONS

Poison exposures and poisonings have increased significantly and have contributed substantially to morbidity and mortality in Israel. The IPIC database is a valuable national resource for the collection and monitoring of poisoning exposure cases. It can be used as a real-time surveillance system for the benefit of public health. It is recommended that reporting to the IPIC become mandatory and its activities be adequately supported by national resources.

Potential input from metabolomics for exploring and understanding the links between environment and health

Humans may be exposed via their environment to multiple chemicals as a consequence of human activities and use of synthetic products. Little knowledge is routinely generated on the hazards of these chemical mixtures. The metabolomic approach is widely used to identify metabolic pathways modified by diseases, drugs, or exposures to toxicants. This review, based on the state of the art of the current applications of metabolomics in environmental health, attempts to determine whether metabolomics might constitute an original approach to the study of associations between multiple, low-dose environmental exposures in humans. Studying the biochemical consequences of complex environmental exposures is a challenge demanding the development of careful experimental and epidemiological designs, in order to take into account possible confounders associated with the high level of interindividual variability induced by different lifestyles. The choices of populations studied, sampling and storage procedures, statistical tools used, and system biology need to be considered. Suggestions for improved experimental and epidemiological designs are described. Evidence indicates that metabolomics may be a powerful tool in environmental health in the identification of both complex exposure biomarkers directly in human populations and modified metabolic pathways, in an attempt to improve understanding the underlying environmental causes of diseases. Nevertheless, the validity of biomarkers and relevancy of animal-to-human extrapolation remain key challenges that need to be properly explored.

The emergency response program at the Agency for Toxic Substances and Disease Registry

As part of our continuing effort to highlight innovative approaches to improving the health and environment of communities, the Journal is pleased to publish a bimonthly column from the U.S. Agency for Toxic Substances and Disease Registry (ATSDR). The ATSDR, based in Atlanta, Georgia, is a federal public health agency of the U.S. Department of Health and Human Services and shares a common office of the Director with the National Center for Environmental Health at the Centers for Disease Control and Prevention (CDC). ATSDR serves the public by using the best science, taking responsive public health actions, and providing trusted health information to prevent harmful exposures and diseases related to toxic substances. The purpose of this column is to inform readers of ATSDR's activities and initiatives to better understand the relationship between exposure to hazardous substances in the environment and their impact on human health and how to protect public health. We believe that the column will provide a valuable resource to our readership by helping to make known the considerable resources and expertise that ATSDR has available to assist communities, states, and others to assure good environmental health practice for all is served.

On dermal exposure assessment

Hazardous chemicals may enter the body by inhalation, ingestion, injection or dermal absorption. These exposure routes constitute the overall exposure burden on the body. Most occupational exposure studies have focused on measurement of the concentration of air-borne contaminants and other possible routes of exposure are often overlooked.Several studies have already highlighted the importance of dermal absorption. However, less development occurred in the assessment of dermal exposures to occupational and environmental contaminants compared to air sampling techniques.This paper intends to highlight the importance of dermal exposure and looks at the methods currently used for its assessment. Advantages and disadvantages of each method in the context of occupational dermal exposure assessment are also outlined. Dermal exposure models, as an easy-to-use and low-cost tool to predict dermal uptake, especially when few or no actual data are available, are also included in this review.

[The dynamics of gender-age indicators of lethality in population of Omsk as a result of acute and chemical intoxications in 2001-2010]

The article demonstrates that in Omsk, during 2001-1010, the indicators of lethality of population as a result of acute chemical intoxications were reliably higher in females. At that, significant decrease of corresponding indicator of lethality in males was observed. In contrary, a slight increase of lethality was established in females. The significant differences in indicators of lethality due to acute chemical intoxications between age groups made it possible to draw a conclusion about the impact of age-related factor to the forecast and outcome of chemical intoxication. This data is to be considered during the development of standards, protocols and treatment algorithms relating to patients with the mentioned pathology.

The road to GHS: worker right-to-know in the 21st century

Of the three communications standards discussed, HI is definitely the outlier, as it emphasizes worker control of the process of identifying hazard and deemphasizes employer control of identification of hazards and dissemination of hazard information. GHS may not be as protective of American workers as HazCom is, but for workers in less-developed countries, where regulation of workplace health and safety is less strong than in the United States, Canada, many countries in Europe, and Japan, GHS--if adequately enforced-will likely represent an improvement in information on chemical hazards in the workplace. American workers may well see a decline in workplace protection against chemical hazards while protection may improve for workers in less-developed countries. This trade-off is part of the ongoing debate about globalization, of which worker protection from chemical hazards should be an important aspect. The next paper in this series will compare the proposed and final versions of GHS, and will discuss possible improvements to GHS to better serve American workers. As OSHA moves forward with the GHS rule, people and organizations concerned with worker right-to-know should consider possible improvements to GHS to better serve workers in the United States and worldwide.

Occupational and environmental exposures among Alaska Native and American Indian people living in Alaska and the Southwest United States

Most occupational and environmental research describes associations between specific occupational and environmental hazards and health outcomes, with little information available on population-level exposure, especially among unique subpopulations. The authors describe the prevalence of self-reported lifetime exposure to nine occupational and environmental hazards among 11,326 American Indian and Alaska Native (AI/AN) adults enrolled in the Education and Research Towards Health (EARTH) Study in the Southwest U.S. and Alaska. The top three hazards experienced by AI/AN people in Alaska were petroleum products, military chemicals, and asbestos. The top three hazards experienced by AI/AN living in the Southwest U.S. were pesticides, petroleum, and welding/silversmithing. The study described here found that male sex, lower educational attainment, AI/AN language use, and living in the Southwest U.S. (vs. Alaska) were all associated with an increased likelihood of hazard exposure. The authors' study provides baseline data to facilitate future exposure-response analyses. Future studies should measure dose and duration as well as environmental hazards that occur in community settings.

Chemical Hazards Emergency Medical Management (CHEMM)

The Chemical Hazards Emergency Medical Management (CHEMM) website from the National Library of Medicine is designed for first responders and medical providers who are planning for and responding to chemical hazards events. It includes pages tailored to the individual interests of specific groups, including first responders, health care providers, mental health professionals, toxicologists, and more. The featured decision support system CHEMM Intelligent Syndromes Tool allows users to identify the chemical a patient was exposed to in a mass casualty event.

[The characteristics of epidemiology of acute exogenous intoxications]

The article pays attention to the actuality of issue of steady increase of numbers of acute chemical intoxications. The data is presented concerning the characteristics of epidemiology of acute chemical intoxications. The need to develop and enhance the specialized toxicological service is emphasized

Centers for Disease Control and Prevention (CDC). Chemical suicides in automobiles--six states, 2006-2010

During a 3-month period in 2008 in Japan, 208 persons committed suicide by mixing household chemicals and, while in a confined space, breathing in the resultant poisonous gas. The large number of similar suicides is believed to have resulted from the posting of directions for generating poisonous gas on the Internet. In addition to claiming the suicide victim, lethal gas generated by intentionally mixing household chemicals can leak from confined spaces, triggering evacuations, and exposing bystanders and first responders to injury. Chemical suicides similar to those in Japan in 2008 have been reported increasingly in the United States, with the majority occurring inside automobiles. To characterize such incidents in the United States, the Agency for Toxic Substances and Disease Registry (ATSDR) analyzed reports of chemical suicides and attempted suicides that occurred in automobiles, using 2006--2009 data from states participating in the Hazardous Substances Emergency Events Surveillance (HSEES) system and 2010 data from states participating in the new National Toxic Substance Incidents Program (NTSIP). This report summarizes the results of that analysis, which found that, during 2006--2010, a total of 10 chemical suicide incidents were reported from six states, resulting in the deaths of nine suicide victims and injuries to four law enforcement officers. When responding to suspected chemical suicide incidents, emergency responders must take precautions to ensure both their safety and the safety of any bystanders in the immediate vicinity.

Maximum cumulative ratio (MCR) as a tool for assessing the value of performing a cumulative risk assessment

Due to the vast number of possible combinations of chemicals to which individuals are exposed and the resource-intensive nature of cumulative risk assessments, there is a need to determine when cumulative assessments are most required. This paper proposes the use of the maximum cumulative ratio (MCR) as a tool for this evaluation. MCR is the ratio of the cumulative toxicity received by an individual from exposure to multiple chemical stressors to the largest toxicity from a single chemical stressor. The MCR is a quantitative measure of the difference in an individual’s toxicity estimated using a chemical-by-chemical approach and using an additive model of toxicity. As such, it provides a conservative estimate of the degree to which individuals’ toxicities could be underestimated by not performing a cumulative risk assessment. In an example application, MCR is shown to be applicable to the evaluation of cumulative exposures involving up to 81 compounds and to provide key insights into the cumulative effects posed by exposures to multiple chemicals. In this example, MCR values suggest that individuals exposed to combinations of chemicals with the largest Hazard Indices were dominated by the contributions of one or two compounds.

Hazards of illicit methamphetamine production and efforts at reduction: data from the hazardous substances emergency events surveillance system

OBJECTIVES

Methamphetamine (meth) is a highly addictive drug of abuse that can easily be made in small illegal laboratories from household chemicals that are highly toxic and dangerous. Meth labs have been found in locations such as homes, outbuildings, motels, and cars. Its production endangers the "cook," neighbors, responders, and the environment. This article describes surveillance data used to examine the emergence and public health impacts of illicit clandestine meth labs, as well as two states' efforts to thwart lab operations and prevent responder injuries.

METHODS

We analyzed data collected from 2001 to 2008 by 18 states participating in the Agency for Toxic Substances and Disease Registry's Hazardous Substances Emergency Events Surveillance (HSEES) Program to examine the occurrence and public health impacts of clandestine meth production.

RESULTS

HSEES data indicate that the majority of clandestine meth lab events occurred in residential areas. About 15% of meth lab events required evacuation. Nearly one-fourth of these events resulted in injuries, with 902 reported victims. Most victims (61%) were official responders, and one-third were members of the general public. Since 2004, with the implementation of local and federal laws and prevention activities, the number of meth lab events has declined. Increased education and training of first responders has led to decreased injuries among police officers, firefighters, and emergency medical personnel.

CONCLUSIONS

HSEES data provided a good data source for monitoring the emergence of domestic clandestine meth production, the associated public health effects, and the results of state and federal efforts to promote actions to address the problem.

Residential proximity to toxic release sites and the implications for low birth weight and premature delivery

The objective of the study discussed in this article was to evaluate the impact of residential proximity to toxic release sites (TRS) and potential implications for low birth weight (LBW) and premature delivery in Shelby County, Tennessee women. The sample (N = 369) included pregnant women who participated in the Blues Project (2007-2009). ArcGIS was used to map the mother's residence at delivery and distance from each of the 10 TRS. Multivariate logistic regression was used to predict LBW and prematurity based on proximity to TRS, while adjusting for probable confounders and effect modifiers. Proximity to Site 8 (odds ratio [OR] = 4.018, confidence interval [CI] = 1.103-14.643) and Site 10 (OR = 2.667, CI = 1.036-6.862) put mothers at increased risk for preterm births. The authors' findings suggest that residential proximity to Site 8 or Site 10 may be a risk factor for premature delivery in Shelby County women.

Deciphering diseases and biological targets for environmental chemicals using toxicogenomics networks

Exposure to environmental chemicals and drugs may have a negative effect on human health. A better understanding of the molecular mechanism of such compounds is needed to determine the risk. We present a high confidence human protein-protein association network built upon the integration of chemical toxicology and systems biology. This computational systems chemical biology model reveals uncharacterized connections between compounds and diseases, thus predicting which compounds may be risk factors for human health. Additionally, the network can be used to identify unexpected potential associations between chemicals and proteins. Examples are shown for chemicals associated with breast cancer, lung cancer and necrosis, and potential protein targets for di-ethylhexyl-phthalate, 2,3,7,8-tetrachlorodibenzo-p-dioxin, pirinixic acid and permethrine. The chemical-protein associations are supported through recent published studies, which illustrate the power of our approach that integrates toxicogenomics data with other data types.

Exposure to environmental chemicals and drugs may have a negative effect on human health. An essential step towards understanding the effect of chemicals on human health is to identify all possible molecular targets of a given chemical. Recently, various network-oriented chemical pharmacology approaches have been published. However, these methods limit the protein prediction to already known molecular drug targets. New findings can for example be made by using high-confidence protein-protein association databases. Here, we describe a generic, computational systems biology model with the aim of understanding the underlying molecular mechanisms of chemicals and the biological pathways they perturb. We present a novel and complementary approach to existing models by integrating toxicogenomics data, chemical structures, protein-protein interaction data, disease information and functional annotation of proteins. The high confidence protein-protein association network proposed reveals unexpected connections between chemicals and diseases or human proteins. We provide literature support to demonstrate the validity of some predictions, and thereby illustrate the power of an approach that integrates toxicogenomics data with other data types.

Activation of Hedgehog signaling by the environmental toxicant arsenic may contribute to the etiology of arsenic-induced tumors

Exposure to the environmental toxicant arsenic, through both contaminated water and food, contributes to significant health problems worldwide. In particular, arsenic exposure is thought to function as a carcinogen for lung, skin, and bladder cancer via mechanisms that remain largely unknown. More recently, the Hedgehog signaling pathway has also been implicated in the progression and maintenance of these same cancers. Based on these similarities, we tested the hypothesis that arsenic may act in part through activating Hedgehog signaling. Here, we show that arsenic is able to activate Hedgehog signaling in several primary and established tissue culture cells as well as in vivo. Arsenic activates Hedgehog signaling by decreasing the stability of the repressor form of GLI3, one of the transcription factors that ultimately regulate Hedgehog activity. We also show, using tumor samples from a cohort of bladder cancer patients, that high levels of arsenic exposure are associated with high levels of Hedgehog activity. Given the important role Hedgehog signaling plays in the maintenance and progression of a variety of tumors, including bladder cancer, these results suggest that arsenic exposure may in part promote cancer through the activation of Hedgehog signaling. Thus, we provide an important insight into the etiology of arsenic-induced human carcinogenesis, which may be relevant to millions of people exposed to high levels of arsenic worldwide.

Environmental toxins and Parkinson's disease: putative roles of impaired electron transport chain and oxidative stress

Despite recent advancements in the biomedical fields, the etiology and pathogenesis of Parkinson's disease (PD) is still poorly understood, though the crucial roles of oxidative stress and impaired mitochondrial respiration have been suggested in the development of PD. The oxidative modification of the proteins of mitochondrial electron transport chain alters their normal function leading to the state of energy crisis in neurons. Exposure of environmental chemicals such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and rotenone in mouse produces the symptoms akin to PD and therefore these neurotoxins are commonly used in experimental studies on PD. Another environmental toxin, paraquat (a commonly used herbicide) has also been implicated with the onset of PD. The neurotoxicity of these chemicals is accompanied by the blockade of electron flow from NADH dehydrogenase to coenzyme Q. The agents with the ability to improve mitochondrial respiration and ATP production have been shown to exert beneficial effects in PD patients as well as in the animal models of PD. This review summarizes the current research implicating the impairment of mitochondrial respiratory chain and the role of environmental toxins in the pathogenesis of PD.

[Registers of health for workers exposed to extremely dangerous toxic chemicals--basis for early diagnosis and prevention of occupational intoxications]

The article deals with results of specification and functioning of a register of health for workers exposed to extremely dangerous toxic chemicals. The authors demonstrated patterns of diseases development in workers according to length of work with toxic chemicals and to work conditions. The identified cause-effect relationships of the diseases development necessitate health registers to minimize negative consequences in work conditions, for early diagnosis and occupational diseases prevention.

Toxic ignorance and right-to-know in biomonitoring results communication: a survey of scientists and study participants

BACKGROUND

Exposure assessment has shifted from pollutant monitoring in air, soil, and water toward personal exposure measurements and biomonitoring. This trend along with the paucity of health effect data for many of the pollutants studied raise ethical and scientific challenges for reporting results to study participants.

METHODS

We interviewed 26 individuals involved in biomonitoring studies, including academic scientists, scientists from environmental advocacy organizations, IRB officials, and study participants; observed meetings where stakeholders discussed these issues; and reviewed the relevant literature to assess emerging ethical, scientific, and policy debates about personal exposure assessment and biomonitoring, including public demand for information on the human health effects of chemical body burdens.

RESULTS

We identify three frameworks for report-back in personal exposure studies: clinical ethics; community-based participatory research; and citizen science 'data judo.' The first approach emphasizes reporting results only when the health significance of exposures is known, while the latter two represent new communication strategies where study participants play a role in interpreting, disseminating, and leveraging results to promote community health. We identify five critical areas to consider in planning future biomonitoring studies.

CONCLUSION

Public deliberation about communication in personal exposure assessment research suggests that new forms of community-based research ethics and participatory scientific practice are emerging.

Occupational exposures and non-Hodgkin's lymphoma: Canadian case-control study

BACKGROUND

The objective was to study the association between Non-Hodgkin's Lymphoma (NHL) and occupational exposures related to long held occupations among males in six provinces of Canada.

METHODS

A population based case-control study was conducted from 1991 to 1994. Males with newly diagnosed NHL (ICD-10) were stratified by province of residence and age group. A total of 513 incident cases and 1506 population based controls were included in the analysis. Conditional logistic regression was conducted to fit statistical models.

RESULTS

Based on conditional logistic regression modeling, the following factors independently increased the risk of NHL: farmer and machinist as long held occupations; constant exposure to diesel exhaust fumes; constant exposure to ionizing radiation (radium); and personal history of another cancer. Men who had worked for 20 years or more as farmer and machinist were the most likely to develop NHL.

CONCLUSION

An increased risk of developing NHL is associated with the following: long held occupations of faer and machinist; exposure to diesel fumes; and exposure to ionizing radiation (radium). The risk of NHL increased with the duration of employment as a farmer or machinist.

[Inquiries to the Norwegian Poisons Information Centre on acute exposures to chemicals and chemical products]

BACKGROUND

The Poisons Information Centre receives many inquiries about acute exposures to chemical products. Our aim was to characterise the frequency and severity of such exposures and to raise awareness of chemicals that rarely cause poisoning, but may lead to serious systemic toxicity even in small amounts.

MATERIAL AND METHODS

Data were collected from inquiries to the Poisons Information Centre in the period 2004-2006 and from the Product Register on the use of selected chemicals.

RESULTS

In 2004-2006, the Poisons Information Centre received 35,802 inquiries regarding acute exposures to chemicals or chemical products. Most of the exposures (72%) were assessed as non-toxic or involving risk of minor poisoning, while only 7.8% were assessed as involving risk of severe poisoning. The substances most frequently involved were cleaning agents, cosmetics/personal care products and hydrocarbon fuels, whereas risk of severe poisoning is related to alkali and hydrocarbon exposures. Poisonings with hydrofluoric acid and glycols/glycol ethers are rare, but the outcome is often severe. As many as 84% of the hydrofluoric acid exposures and 36% of the ingestions of ethylene glycol by children were assessed as involving risk of moderate or severe poisoning.

INTERPRETATION

Exposure to chemicals or chemical products is frequent, but rarely leads to severe poisonings. Data from inquiries to the Poisons Information Centre are representative of the chemical exposure conditions. It is important to have detailed product information readily available to assure correct treatment after exposure incidents.

[Contemporary state of using specialized food products to correct metabolic processes in chemical intoxication (review of literature)]

The article deals with topics associated with contemporary state of using specialized food products to correct metabolic processes in intoxication with various chemicals.

Acute hazardous substance releases resulting in adverse health consequences in children: Hazardous Substances Emergency Events Surveillance system, 1996-2003

Because of their small size and ongoing organ development, children may be more susceptible than adults to the harmful effects of toxic chemicals. The objective of the study reported here was to identify frequent locations, released substances, and factors contributing to short-term chemical exposures associated with adverse health consequences experienced by children. The study examined the Hazardous Substances Emergency Events Surveillance (HSEES) system data from 1996-2003. Eligible events involved the acute release of a hazardous substance associated with at least one child being injured. The study found that injured children were predominantly at school, home, or a recreational center when events took place. School-related events were associated with the accidental release of acids and the release of pepper spray by pranksters. Carbon monoxide poisonings occurring in the home, retail stores, entertainment facilities, and hotels were responsible for about 10 percent of events involving child victims. Chlorine was one of the top chemicals harmful to children, particularly at public swimming pools. Although human error contributed to the majority of releases involving child victims, equipment failure was responsible for most chlorine and ammonia releases. The authors conclude that chemical releases resulting in injury to children occur mostly in schools, homes, and recreational areas. Surveillance of acute hazardous chemical releases helped identify contributing causes and can guide the development of prevention outreach activities. Chemical accidents cannot be entirely prevented, but efforts can be taken to provide safer environments in which children can live, learn, and play. Wide dissemination of safety recommendations and education programs is required to protect children from needless environmental dangers.

Minamata disease revisited: An update on the acute and chronic manifestations of methyl mercury poisoning

The first well-documented outbreak of acute methyl mercury (MeHg) poisoning by consumption of contaminated fish occurred in Minamata, Japan, in 1953. The clinical picture was officially recognized and called Minamata disease (MD) in 1956. However, 50 years later there are still arguments about the definition of MD in terms of clinical symptoms and extent of lesions. We provide a historical review of this epidemic and an update of the problem of MeHg toxicity. Since MeHg dispersed from Minamata to the Shiranui Sea, residents living around the sea were exposed to low-dose MeHg through fish consumption for about 20 years (at least from 1950 to 1968). These patients with chronic MeHg poisoning continue to complain of distal paresthesias of the extremities and the lips even 30 years after cessation of exposure to MeHg. Based on findings in these patients the symptoms and lesions in MeHg poisoning are reappraised. The persisting somatosensory disorders after discontinuation of exposure to MeHg were induced by diffuse damage to the somatosensory cortex, but not by damage to the peripheral nervous system, as previously believed.

From lead to manganese through mercury: mythology, science, and lessons for prevention

BACKGROUND

Lead (Pb), mercury (Hg), and manganese (Mn) are well-known neurotoxic metals. The knowledge of toxicity was developed through an extensive amount of research, starting with lead and mercury and proceeding today with manganese. Unfortunately, the consequent implementation of preventive measures was generally delayed, causing important negative effects to the exposed populations.

METHODS

A review and historical reconstruction of the research development that yielded modern understanding of lead and mercury neurotoxicity was conducted to derive useful lessons for the prevention of manganese neurotoxicity.

RESULTS

Medieval alchemists named planets and metals from gods since they were already aware of the toxicity and the adverse effects caused by lead and mercury. Historical lessons learned from these two metals may help to avoid the repetition of further mistakes regarding other neurotoxic metals like manganese. The knowledge and experience on the toxicokinetics and toxicodynamics of lead and mercury is useful and valuable to identify a proper approach to "safe" exposure levels for manganese.

CONCLUSIONS

Further information is still needed on the early neurotoxic and neurobehavioral effects after prolonged exposure to very low doses of lead, mercury, and manganese. Nevertheless, according to the precautionary principle, effective preventive measures should be already undertaken to prevent the onset of more severe health effects in the population. This is the most important lesson to be learned and applied from more than 30 years of occupational and environmental neurotoxicology of metals.

Controversy: neonatal exposure to plasticizers in the NICU

This article presents a review of extant literature that informs our current understanding of the effects of di-(2-ethylhexyl) phthalate (DEHP) exposure on neonates. Phthalates such as DEHP add flexibility to plastics. DEHP is a major component in the manufacturing of polyvinyl chloride devices commonly used in the healthcare setting. Premature and critically ill neonates and infants in the NICU are exposed to DEHP and may be at an increased risk for adverse health outcomes as a result. DEHP has been shown to be a developmental and endocrine disrupting toxicant and is a major component in polyvinyl chloride plastics, which are commonly found in medical equipment used in the NICU. Potential toxicities to infants in the NICU are a concern because infants' small body size and compromised physical condition necessitate a multitude of medical interventions, each increasing exposure levels. Expanding nurses' knowledge regarding DEHP research is important for implementing a precautionary approach to reduce DEHP exposure among NICU patients.