Department of Environmental Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW 2109, Australia.
Department of Environmental Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW 2109, Australia.
Environ Int. 2019 Jun;127:340-352. doi: 10.1016/j.envint.2019.01.062. Epub 2019 Apr 4.
The city of Port Pirie in South Australia has been a world leading centre for lead and zinc smelting and processing since 1889 that continues to cause contamination of its environment and resident population. This study quantifies the effect of lead and SO emissions from Nyrstar Port Pirie Pty Ltd's smelter on blood lead and respiratory health outcomes, respectively, and establishes what air quality values are required to better protect human health.
Blood lead and emergency department presentation data collected by South Australia Health (SA Health) and lead in air and SO data collected by the South Australian Environment Protection Authority (SAEPA) were obtained and analysed to quantify health outcomes due to smelter emissions in Port Pirie. Regression analysis was used to assess the relationship between the concentration of lead in air and children's blood lead levels between the years of available data: 2003 to 2017. Ambient SO concentrations (SAEPA) measured continuously between 2008 and 2018 were 24-hour averaged and compared to daily local emergency department respiratory presentation rates (available from July 2012 to October 2018). Rates of emergency department respiratory presentations at Port Pirie and regional comparators were calculated as age-standardised rates.
The data show that increases in ambient SO concentrations are associated with increased rates of emergency department respiratory presentations of Port Pirie residents, in which children are over-represented. The 30-day rolling average of respiratory presentations was significantly associated (p < 0.05) with incremental increases in SO. Analysis of the relationship between lead in air and blood lead shows that annual geometric mean air lead concentrations need to be <0.11 μg/m to ensure the geometric mean blood lead of Port Pirie children under 5 years is ≤5 μg/dL. For children aged 24 months, lead in air needs to be no greater than 0.082 μg/m (annual geometric mean) to ensure geometric mean blood lead does not exceed 5 μg/dL.
Current smelting emissions continue to pose a clear risk of harm to Port Pirie children. Allowable emissions must be lowered significantly to limit adverse childhood health outcomes including respiratory illness and IQ, academic achievement and socio-behavioural problems that are associated with lead exposure at levels experienced by Port Pirie children. Current SO levels are likely to be responsible for increased rates of emergency department respiratory presentations in Port Pirie compared with other South Australian locations. As a minimum, Australian SO air quality standards need to be enforced in Port Pirie to better protect human health. Lead in air needs to be approximately 80% lower than the current national standard (0.5 μg/m) to ensure that the geometric blood lead of children under 5 years is less than or equal to 5 μg/dL.
自 1889 年以来，南澳大利亚州的皮里港一直是世界领先的铅和锌冶炼和加工中心，其持续的污染对当地环境和居民健康造成了影响。本研究分别量化了 Nyrstar Port Pirie Pty Ltd 冶炼厂的铅和 SO 排放对血液铅和呼吸道健康结果的影响，并确定了需要达到什么样的空气质量值才能更好地保护人类健康。
收集了南澳大利亚卫生局（SA Health）的血液铅和急诊就诊数据以及南澳大利亚环境保护局（SAEPA）的空气中铅和 SO 数据，以量化皮里港冶炼厂排放对健康的影响。回归分析用于评估可用数据年份（2003 年至 2017 年）中空气中铅浓度与儿童血液铅水平之间的关系。2008 年至 2018 年连续测量的环境 SO 浓度（SAEPA）进行了 24 小时平均处理，并与每日当地急诊就诊呼吸道就诊率进行了比较（可从 2012 年 7 月至 2018 年 10 月获得）。皮里港和区域对照的急诊就诊呼吸道就诊率按年龄标准化计算。
数据表明，环境 SO 浓度的增加与皮里港居民急诊就诊呼吸道疾病的增加有关，其中儿童的发病率更高。30 天滚动平均呼吸道就诊率与 SO 的增量显著相关（p<0.05）。空气中铅与血液铅之间关系的分析表明，为确保皮里港 5 岁以下儿童的血液铅几何均数≤5μg/dL，每年的几何均数空气铅浓度必须<0.11μg/m。对于 24 个月大的儿童，空气中的铅需要不超过 0.082μg/m（年几何均值），以确保血液铅的几何均数不超过 5μg/dL。
目前的冶炼排放仍对皮里港儿童的健康构成明显威胁。为了限制与儿童接触铅相关的呼吸道疾病和智商、学业成绩和社会行为问题等不良儿童健康后果，必须大幅降低可允许的排放量。目前的 SO 水平可能导致皮里港急诊就诊呼吸道疾病的发病率高于南澳大利亚其他地区。作为最低要求，需要在皮里港执行澳大利亚 SO 空气质量标准，以更好地保护人类健康。空气中的铅需要比目前的国家标准（0.5μg/m）低约 80%，以确保 5 岁以下儿童的血液铅几何均数小于或等于 5μg/dL。
