Prevalence Rates of Borrelia burgdorferi (Spirochaetales: Spirochaetaceae), Anaplasma phagocytophilum (Rickettsiales: Anaplasmataceae), and Babesia microti (Piroplasmida: Babesiidae) in Host-Seeking Ixodes scapularis (Acari: Ixodidae) from Pennsylvania.

The etiological agents responsible for Lyme disease (Borrelia burgdorferi), human granulocytic anaplasmosis (Anaplasma phagocytophilum), and babesiosis (Babesia microti) are primarily transmitted by the blacklegged tick, Ixodes scapularis Say. Despite Pennsylvania having in recent years reported the highest number of Lyme disease cases in the United States, relatively little is known regarding the geographic distribution of the vector and its pathogens in the state. Previous attempts at climate-based predictive modeling of I. scapularis occurrence have not coincided with the high human incidence rates in parts of the state. To elucidate the distribution and pathogen infection rates of I. scapularis, we collected and tested 1,855 adult ticks statewide from 2012 to 2014. The presence of I. scapularis and B. burgdorferi was confirmed from all 67 Pennsylvania counties. Analyses were performed on 1,363 ticks collected in the fall of 2013 to avoid temporal bias across years. Infection rates were highest for B. burgdorferi (47.4%), followed by Ba. microti (3.5%) and A. phagocytophilum (3.3%). Coinfections included B. burgdorferi+Ba. microti (2.0%), B. burgdorferi+A. phagocytophilum (1.5%) and one tick positive for A. phagocytophilum+Ba. microti. Infection rates for B. burgdorferi were lower in the western region of the state. Our findings substantiate that Lyme disease risk is high throughout Pennsylvania.

Evaluating the health significance of hazardous air pollutants using monitoring data.

OBJECTIVE: Though many contaminants are released into the atmosphere, in the US only six air pollutants-ozone, particulate matter, sulfur dioxide, carbon monoxide, nitrogen dioxide, and lead-are closely monitored and carefully assessed for health significance. Other pollutants, even if highly toxic, are neither widely monitored nor routinely assessed at the national level. The goal of this study was to analyze the availability of information needed to characterize the health significance of hazardous air pollutants, focusing on urban areas in California. METHODS: The authors compared different approaches to identifying which contaminants should be considered hazardous air pollutants of potential health concern; reviewed the availability of toxicity values for these pollutants; and analyzed the usefulness of air monitoring data from California agencies for determining populations risks, by comparing method detection limits with health benchmarks. RESULTS: Approaches to identifying air contaminants of possible health concern differ. Toxicity values are not available for many hazardous air pollutants, including those identified in the Clean Air Act. In California, monitoring data are available for many, though not all, pollutants of concern. Monitoring methods for several pollutants do not have adequate sensitivity to detect all relevant concentrations. CONCLUSION: The information necessary to fully assess the health significance of hazardous air pollutants is not currently available.

Regulatory reform proposals and the public health.

The U.S. Congress is considering legislation that would change policy for environmental health in important ways. Current approaches have been criticized for addressing the wrong set of priorities and consuming too many resources. The legislation requires additional analyses and sets new decision criteria to be applied to federal agency actions taken to protect the environment and public health. Close review of the legislation suggests that though it is intended to address identified problems, it is unlikely to lead to an improved basis for public policy and is likely to paralyze the regulatory process. Reform proposals that reduce rather than increase fragmentation of decision-making and that address problems comprehensively rather than selectively are needed.

Evaluating health risks from occupational exposure to pesticides and the regulatory response.

In this study, we used measurements of occupational exposures to pesticides in agriculture to evaluate health risks and analyzed how the federal regulatory program is addressing these risks. Dose estimates developed by the State of California from measured occupational exposures to 41 pesticides were compared to standard indices of acute toxicity (LD50) and chronic effects (reference dose). Lifetime cancer risks were estimated using cancer potencies. Estimated absorbed daily doses for mixers, loaders, and applicators of pesticides ranged from less than 0.0001% to 48% of the estimated human LD50 values, and doses for 10 of 40 pesticides exceeded 1% of the estimated human LD50 values. Estimated lifetime absorbed daily doses ranged from 0.1% to 114,000% of the reference doses developed by the U.S. Environmental Protection Agency, and doses for 13 of 25 pesticides were above them. Lifetime cancer risks ranged from 1 per million to 1700 per million, and estimates for 12 of 13 pesticides were above 1 per million. Similar results were obtained for field workers and flaggers. For the pesticides examined, exposures pose greater risks of chronic effects than acute effects. Exposure reduction measures, including use of closed mixing systems and personal protective equipment, significantly reduced exposures. Proposed regulations rely primarily on requirements for personal protective equipment and use restrictions to protect workers. Chronic health risks are not considered in setting these requirements. Reviews of pesticides by the federal pesticide regulatory program have had little effect on occupational risks. Policy strategies that offer immediate protection for workers and that are not dependent on extensive review of individual pesticides should be pursued.