Reported health conditions in animals residing near natural gas wells in southwestern Pennsylvania.

Natural gas extraction activities, including the use of horizontal drilling and hydraulic fracturing, may pose potential health risks to both human and animal populations in close proximity to sites of extraction activity. Because animals may have increased exposure to contaminated water and air as well as increased susceptibility to contaminant exposures compared to nearby humans, animal disease events in communities living near natural gas extraction may provide "sentinel" information useful for human health risk assessment. Community health evaluations as well as health impact assessments (HIAs) of natural gas exploration should therefore consider the inclusion of animal health metrics in their assessment process. We report on a community environmental health survey conducted in an area of active natural gas drilling, which included the collection of health data on 2452 companion and backyard animals residing in 157 randomly-selected households of Washington County, Pennsylvania (USA). There were a total of 127 reported health conditions, most commonly among dogs. When reports from all animals were considered, there were no significant associations between reported health condition and household proximity to natural gas wells. When dogs were analyzed separately, we found an elevated risk of 'any' reported health condition in households less than 1km from the nearest gas well (OR = 3.2, 95% CI 1.07-9.7), with dermal conditions being the most common of canine disorders. While these results should be considered hypothesis generating and preliminary, they suggest value in ongoing assessments of pet dogs as well as other animals to better elucidate the health impacts of natural gas extraction on nearby communities.

Development of a test battery to identify older drivers at risk for self-reported adverse driving events.

OBJECTIVES: The purposes of this study were (1) to develop a battery of tests that assessed a wide range of functional abilities relevant to driving yet could be performed in a clinician's office and (2) to determine which of these tests were most closely associated with self-reported adverse driving events. DESIGN: A cohort study. SETTING: An urban community. PARTICIPANTS: Participants were drawn from the Project Safety cohort, a probability sample of noninstitutionalized older persons in New Haven, Connecticut, initiated in 1989. The current study included surviving, active drivers in the cohort (N=125). MEASURES: The test battery assessed visual, cognitive, and physical abilities potentially relevant to driving, and was administered in participants' homes by trained interviewers between October 1994 and July 1995. Outcome measures included the self-report of a crash, moving violation, or being stopped by police in any Project Safety interview since the inception of the cohort. Analyses compared performance on the elements of the test battery with participants' histories of adverse driving events. RESULTS: Of the 125 drivers, 50 (40%) had reported an adverse event in a mean period of 5.76 (+/-.25) years before the current interview. The elements of the test battery independently associated with a history of events, adjusting for driving frequency, included near visual acuity worse than 20/40 (adjusted odds ratio 11.90), limited neck rotation (OR 6.10), and poor performance on a test of visual attention, the number cancellation task (OR 3.00). The resulting regression equation yielded a sensitivity of 80%, a specificity of 55%, and an area under the curve of .75 by receiver operating characteristic analysis. CONCLUSION: These findings suggest it may be possible to identify individuals potentially at risk for self-reported adverse driving events using simple tests of functional ability. If validated, such an approach could be used to identify individuals who need a more detailed assessment of functional abilities to determine the severity and etiology of impairments, and their effect on driving performance, as well as possible interventions to correct or compensate for the impairments.

Diisocyanate-exposed auto body shop workers: a one-year follow-up.

BACKGROUND: Diisocyanates currently are the most commonly identified cause of occupational asthma in industrialized countries. Auto body shops, a common hexamethylene diisocyanate (HDI) exposure setting, are difficult to study due to their small size and episodic exposures. OBJECTIVES: A 1-year follow-up was undertaken as an adjunct to the cross-sectional SPRAY study (Survey of Painters & Repairers of Auto bodies by Yale) to investigate the effects of HDI on auto body shop workers over time and whether or not the healthy worker effect may exist in this industry. METHODS AND RESULTS: Forty-eight workers from seven shops were re-contacted. Thirty-four subjects who stayed at the same shop and 11 who left their original shop participated. No statistically significant changes in physiology, symptoms, and immunologic responses from baseline to follow-up were noted. However, significant differences between those who left the shops and those who stayed were noted. Those who left were younger, less experienced in the industry, and more likely to have a history of asthma (23 vs. 3%; P < 0.05), bronchial hyper-responsiveness (23 vs. 9%), HDI-specific IgG (64 vs. 29%; P < 0.05), and HDI-specific proliferation (S.I. 2.0 vs. 1.3; P < 0.05). CONCLUSIONS: The differences in workers who stayed at their shop compared to those who left, combined with the low asthma prevalence and high job turnover rate, all suggest that a healthy worker effect may exist in the auto body industry, and may in part account for the low prevalence of asthma noted in SPRAY and other cross-sectional studies of diisocyante workers.

Subclinical immunologic and physiologic responses in hexamethylene diisocyanate-exposed auto body shop workers.

BACKGROUND: Diisocyanates are potent sensitizing agents and currently the most commonly identified cause of occupational asthma in industrialized countries. However, diisocyanate asthma is difficult to diagnose and exposure and host risk factors are unclear. Auto body shops, one of the most common hexamethylene diisocyanate (HDI) exposure settings, are particularly difficult to study due to their small size and episodic exposures. Surveillance studies of such workers are limited. OBJECTIVES: We have initiated a cross-sectional field epidemiologic study, Survey of Painters and Repairers of Auto bodies by Yale (SPRAY), to characterize the effects of diisocyanate exposures on actively employed auto body shop workers. Methods and Results We present here questionnaire, physiologic, immunologic, and exposure data on 75 subjects enrolled in the study. No overt cases of clinically apparent diisocyanate asthma were identified based on spirometry, methacholine challenge, peak flows, and symptoms. HDI-specific lymphocyte proliferation was present in 30% of HDI-exposed workers and HDI-specific IgG in 34% of HDI-exposed workers, but they were not associated. HDI-specific IgE was detected in two workers. HDI-specific lymphocyte proliferation, increased methacholine responsiveness, and symptoms of chest tightness and shortness of breath were more common in the most heavily HDI-exposed workers, the painters. More long-term follow-up of this cohort should clarify the significance of these HDI-specific immunologic responses, physiologic changes, and symptoms. CONCLUSIONS: These findings demonstrate the presence of HDI-specific immune responses in a large proportion of healthy HDI-exposed workers.