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Given the increase in wildfire intensity and frequency worldwide, prescribed burning is becoming a more common and widespread practice. Prescribed burning is a fire management tool used to reduce fuel loads for wildfire suppression purposes and occurs on an annual basis in many parts of the world. Smoke from prescribed burning can have a substantial impact on air quality and the environment. Prescribed burning is a significant source of fine particulate matter (PM2.5aerodynamic diameter < 2.5µm) and these particulates are found to be consistently elevated during smoke events. Due to their fine nature PM2.5are particularly harmful to human health. Here we discuss the impact of prescribed burning on air quality particularly focussing on PM2.5. We have summarised available case studies from Australia including a recent study we conducted in regional Victoria, Australia during the prescribed burning season in 2013. The studies reported very high short-term (hourly) concentrations of PM2.5during prescribed burning. Given the increase in PM2.5concentrations during smoke events, there is a need to understand the influence of prescribed burning smoke exposure on human health. This is important especially since adverse health impacts have been observed during wildfire events when PM2.5concentrations were similar to those observed during prescribed burning events. Robust research is required to quantify and determine health impacts from prescribed burning smoke exposure and derive evidence based interventions for managing the risk. Implications: Given the increase in PM2.5 concentrations during PB smoke events and its impact on the local air quality, the need to understand the influence of PB smoke exposure on human health is important. This knowledge will be important to inform policy and practice of the integrated, consistent, and adaptive approach to the appropriate planning and implementation of public health strategies during PB events. This will also have important implications for land management and public health organizations in developing evidence based objectives to minimize the risk of PB smoke exposure. [ABSTRACT FROM AUTHOR]

A large number of drinking water supplies worldwide have greater than 50 μg l  - 1 inorganic arsenic in drinking water, and there is increasing pressure to reduce concentrations. Few studies have specifically considered low concentrations of arsenic in water supplies and the significance of other factors which may contribute to increased exposure. This study aimed to investigate risk factors for increased urinary inorganic arsenic concentrations, in a population exposed to 10 - 100 μg l  - 1 of arsenic in drinking water, as well as a control population with lower arsenic concentrations in their drinking water. Inorganic arsenic in urine was used as the measure of exposure. The median drinking water arsenic concentration in the exposed population was 43.8 μg l  - 1 (16.0 - 73 μg l  - 1 ) and less than the analytical limit of detection of 1 μg l  - 1 ( < DL) (range < DL - 8.0 μg l  - 1 ) in the control group. The geometric mean urinary inorganic arsenic concentration for the exposed group was 4.24 μg l  − 1 (range < DL - 18.8 μg l  - 1 ) and for the control group was 1.18 μg l  − 1 ( < DL - 4.49 μg l  - 1 ). In a random effects linear regression model, drinking water was the significant predictor of urinary inorganic arsenic concentrations with factors such as age, season and drinking water consumption important risk factors. These results show that concentrations of arsenic in drinking water, even at lower concentrations, make an important contribution to exposure. Further work is required to define the potential for absorption at these lower levels. [ABSTRACT FROM AUTHOR]

Confidence in dose-response relationships arising from occupational studies is dependent upon the reliability and validity of relevant exposure and morbidity estimates. Often self-reported occupational histories are a surrogate for direct exposure measures, and self-report of symptoms serves a similar purpose in place of more objective measures of morbidity. Unfortunately, there are few methods for validating either of these sources of information. This study attempts to evaluate the reproducibility of a survey instrument, and resulting cumulative exposure estimates, utilized in a study of work-related respiratory morbidity in the aluminum industry. The survey instrument comprised measures of pulmonary function, atopic status, smoking, occupational history, and respiratory symptoms. A Task Exposure Matrix was used to estimate exposure categories and cumulative exposure scores. Two groups of employees were administered the survey instrument on two separate occasions. Group A (n = 74) completed their two surveys more than ten weeks apart and Group B (n = 43) completed their surveys less than two weeks apart. Reproducibility was assessed using Cohen's Kappa for categorically measured outcome measures and intraclass correlation coefficients for continuously measured outcomes. Agreement across most variables, for both groups, was generally high. Repeatability of self-reported respiratory symptoms ranged from 70 to 98 percent (Group A) and 88 to 100 percent (Group B). Cumulative exposure scores were highly reproducible, despite some discrepancies in the self-reported occupational histories across interviews, with most of the calculated intraclass r scores exceeding 0.8. These results give strength to studies reporting dose-response relationships derived from similarly collected data. Reproducibility of the survey data was enhanced by use of standardized questionnaire material, consistent interview structure, and calibrated equipment for objective observation. In particular the authors recommend use of a company job dictionary to optimize reproducibility of self-reported occupational information. [ABSTRACT FROM AUTHOR]

This study investigated adverse skin and eye effects in swimmers using pools with three different disinfection systems (chlorine, chlorine/ozone and bromine/ozone) and monitored water quality parameters that may be related to adverse health effects. A cross-sectional study of 770 children swimming in three school pools was carried out over a 4 week period in November 1994 using a postal questionnaire. Physico-chemical and bacteriological parameters of water quality were monitored on a weekly basis. Responses were obtained for 385 swimmers. Skin rashes with an onset less than 24 h after swimming in the school pool were reported by 4–8% of swimmers. Compared with the bromine/ozone pool, the odds ratio (OR) of having a rash that started less than 24 h after pool use was 1.91 (CI 0.71–5.10) for the chlorine pool and 1.88 (CI 0.61–5.81) for the chlorine/ozone pool. Adjustment for possible confounders made no significant differences to these results. Eye redness, itch or irritation was reported by 23–33% of swimmers and 24% of non-swimmers, and wearing swimming goggles had a protective effect (OR 0.40; CI 0.24, 0.65). Disinfectant levels were more consistently maintained in the pools with automatically controlled systems. The bromine disinfection system was not associated with a greater risk of the development of skin rashes than other disinfection systems, but the numbers were small, and need to be interpreted with caution. [ABSTRACT FROM AUTHOR]