Evaluating Risks to Terrestrial Wildlife from Environmental Fluoride

Information and approaches to evaluating health risks to terrestrial wildlife from fluoride contamination in the environment are few in the literature. We use environmental field data from a phosphate ore processing site, toxicity reference values (TRVs), and bioaccumulation factors relative to site conditions to develop risk-based concentrations (RBCs) for total fluoride in terrestrial biota and soil. RBCs were derived specifically for forage that are protective of terrestrial mammalian and avian ecological receptors through multiple exposure pathways, and which can be used to evaluate site remediation or as environmental monitoring action levels. Following review of the literature, we recommend fluoride TRVs for mammalian and avian wildlife, and bioavailability factors for estimating exposures related to aerial deposition of fluoride and fluoride gases. For large ungulates, information on fluoride bioavailability from feed and soil, and related effects thresholds, are summarized from studies on grazing livestock. The resultant RBCs for fluoride in forage range from 14 to 63 mg/kg dry weight, based on no-effect and low-effect concentrations, respectively. These concentrations bracket most state, provincial, and international regulatory standards of vegetation levels for protection of livestock and wildlife.     

Potential Importance of Inhalation Exposures for Wildlife Using Screening-Level Ecological Risk Assessment

Ecological risk assessments (ERAs) have largely ignored exposure to wildlife via inhalation on the assumption that it is negligible compared to the ingestion route of exposure. The assessment of inhalation risk also has been limited due to a paucity of relevant ecotoxicity data. This article presents toxicity reference values (TRVs) for small mammals based on chronic or subchronic exposure studies for a range of organic and trace metal contaminants and ecologically relevant inhalation endpoints. Potential risk to small mammals due to ingestion and inhalation exposure were compared in two hypothetical air emission scenarios for a point source (incinerator) and non-point source emissions (vehicular emissions). Using two screening-level ERAs, we conclude that it may now be time to reconsider inhalation risk to wildlife in the case of atmospheric emissions of some metals and volatile organic compounds (VOCs). In the case of birds, the toxicological database remains too small to assess risks via this pathway. However, for mammals, we suggest that inhalation exposures to contaminants such as cadmium, benzene, and other VOCs could be important.     

Occupational and Environmental Exposures Associated with Testicular Germ Cell Tumours: Systematic Review of Prenatal and Life-Long Exposures

Background

Testicular germ cell tumours (TGCT) are the most common cancers in men aged between 15 and 44 years and the incidence has increased steeply over the past 30 years. The rapid increase in the incidence, the spatial variation and the evolution of incidence in migrants suggest that environmental risk factors play a role in TGCT aetiology. The purpose of our review is to summarise the current state of knowledge on occupational and environmental factors thought to be associated with TGCT.

Methods

A systematic literature search of PubMed. All selected articles were quality appraised by two independent researchers using the ‘Newcastle-Ottawa Quality Assessment Scale’.

Results

After exclusion of duplicate reports, 72 relevant articles were selected; 65 assessed exposure in adulthood, 7 assessed parental exposures and 2 assessed both. Associations with occupation was reported for agricultural workers, construction workers, firemen, policemen, military personnel, as well as workers in paper, plastic or metal industries. Electromagnetic fields, PCBs and pesticides were also suggested. However, results were inconsistent and studies showing positive associations tended to had lower quality ranking using the assessment scale (p=0.02).

Discussion

Current evidence does not allow concluding on existence of any clear association between TGCT and adulthood occupational or environmental exposure. The limitations of the studies may partly explain the inconsistencies observed. The lack of association with adulthood exposure is in line with current hypotheses supporting the prenatal origin of TGCT. Future research should focus on prenatal or early life exposure, as well as combined effect of prenatal and later life exposure. National and international collaborative studies should allow for more adequately powered epidemiological studies. More sophisticated methods for assessing exposure as well as evaluating gene–environment interactions will be necessary to establish clear conclusion.     

Cultural Identity Among Afghan and Iraqi Traumatized Refugees: Towards a Conceptual Framework for Mental Health Care Professionals

Cultural identity in relation with mental health is of growing interest in the field of transcultural psychiatry. However, there is a need to clarify the concept of cultural identity in order to make it useful in clinical practice. The purpose of this study is to unravel the complexity and many layers of cultural identity, and to assess how stress and acculturation relate to (changes in) cultural identity. As part of a larger study about cultural identity, trauma, and mental health, 85 patients from Afghanistan and Iraq in treatment for trauma-related disorders were interviewed with a Brief Cultural Interview. The interviews were analysed through qualitative data analysis using the procedures of grounded theory. The analysis resulted in three domains of cultural identity: personal identity, ethnic identity and social identity. Within each domain relationships with stress and acculturation were identified. The results offer insight into the intensity of changes in cultural identity, caused by pre-and post-migration stressors and the process of acculturation. Based on the research findings recommendations are formulated to enhance the cultural competency of mental health workers.     

Occupational Health Practice

The working status of 1165 patients aged 59 years or less (mean 49.8 years) was evaluated 7 to 77 months (mean 36 months) after aortocoronary bypass surgery. Although 76% of the patients eventually returned to work, only 56% were working 6 months after their operation. The proportion of patients working peaked at 2 years after the operation (at 66%) and decreased progressively to 56% at 4 years and 53% at 5 years without ever reaching the proportions that applied 12 and 6 months before the operation (84% and 69% respectively). Multivariate analysis identified three socioeconomic and three clinical variables as predicting the working status at 6 months and at yearly points during the first 4 years after the operation. Of the socioeconomic variables analysed, preoperative unemployment of long duration, a preoperative occupation that required strenuous physical effort and a low level of education were, in that order, the strongest predictors of postoperative unemployment. Among the clinical variables, associated noncardiovascular illness and the severity and duration of angina pectoris independently influenced the patients'' post-operative working status. The authors conclude that modification of some of these variables should by attempted both before and after aortocoronary bypass surgery to see whether the rate of return to employment after the operation can be improved in selected patients.     

Assessing Children's Exposures and Risks to Drinking Water Contaminants: A Manganese Case Study

Background: Compared to adults, children maybe more highly exposed to toxic substances in drinking water because they consume more water per unit of body weight. The U.S. Environmental Protection Agency (USEPA) has developed new guidance for selecting age groups and age-specific exposure factors for assessing children's exposures and risks to environmental contaminants. Research Aim: To demonstrate the application and importance of applying age-specific drinking water intake rates, health reference values, and exposure scenarios when assessing drinking water exposures because these approaches illustrate the potential for greater potential for adverse health effects among children. Methods: manganese, an essential nutrient and neurotoxicant, was selected as a case study and chemical of potential concern for children's health. A screening-level risk assessment was performed using age-specific drinking water intake rates and manganese concentrations from U.S. public drinking water systems. Results: When age-specific drinking water intake rates are used to calculate dose, formula-fed infants receive the highest dose of manganese from drinking water compared to all other age groups. Estimated hazard quotients suggest adverse health effects are possible. Use of USEPA's standardized childhood age groups and childhood exposure factors significantly improves the understanding of childhood exposure and risks.