Department of Pharmacology, Tulane University School of Medicine, 1430 Tulane Ave., New Orleans, LA 70112, USA.
School of Geosciences, University of Louisiana,104 East University Avenue, Lafayette, LA 70504, USA.
Int J Environ Res Public Health. 2021 Sep 18;18(18):9863. doi: 10.3390/ijerph18189863.
In the small city of St. John's, NL (2020 population ~114,000), 100% of the soils of the pre-1926 properties exceeded the Canadian soil Pb standard, 140 mg/kg. The Pb was traced to high-Pb coal ash used for heating and disposed on the soils outside. Analytical instruments became available in the late 1960s and 1970s and were first used for blood Pb and clinical studies and repurposed for measuring environmental Pb. The environmental research part of this study compared four common soil Pb analysis methods on the same set (N = 96) of St. John's soil samples. The methods: The US EPA method 3050B, portable X-ray fluorescence spectrometry (pXRF), The Chaney-Mielke leachate extraction (1 M nitric acid), and the relative bioaccessibility leaching procedure (US EPA method 1340). Correlation is not the same as agreement ℜ. There is strong agreement (Berry-Mielke's Universal ℜ) among the four soil Pb analytical methods. Accordingly, precaution is normally advisable to protect children from the high-Pb garden soils and play areas. A public health reality check by Health Canada surveillance of St. John's children (N = 257) noted remarkably low blood Pb. The low blood Pb of St. John's' children is contrary to the soil Pb results. Known urban processes causing the rise of environmental Pb and children's Pb exposure includes particle size, aerosol emission by traffic congestion, and quantities of leaded petrol during the 20th century. Smaller cities had minor traffic congestion and limited combustion particles from leaded petrol. From the perspective of the 20th century era of urban Pb pollution, St. John's, NL, children have blood Pb characteristics of a small city.
在新斯科舍省的圣约翰市（2020 年人口约 114000 人），1926 年以前的房产土壤中，有 100%的土壤超过了加拿大土壤铅标准，即 140 毫克/千克。这些铅来自用于取暖的高铅煤灰，这些煤灰被倾倒在外面的土壤上。分析仪器在 20 世纪 60 年代末和 70 年代开始投入使用，最初用于测量血液中的铅含量和进行临床研究，后来被重新用于测量环境中的铅含量。本研究的环境研究部分比较了四种常用的土壤铅分析方法在同一组（N=96）圣约翰土壤样本上的结果。这些方法是：美国环保署 3050B 方法、便携式 X 射线荧光光谱仪（pXRF）、Chaney-Mielke 浸提（1M 硝酸）和相对生物可利用性浸出程序（美国环保署 1340 方法）。相关性并不等同于一致性。这四种土壤铅分析方法之间具有很强的一致性（Berry-Mielke 通用一致性指数）。因此，通常需要采取预防措施，保护儿童免受高铅花园土壤和游乐区的影响。加拿大卫生部对圣约翰市儿童（N=257）进行了监测，发现他们的血液铅含量非常低，这对公共健康现实情况进行了一次检查。圣约翰市儿童的低血铅与土壤铅结果相矛盾。已知导致环境铅和儿童铅暴露增加的城市进程包括颗粒大小、交通拥堵引起的气溶胶排放，以及 20 世纪含铅汽油的数量。较小的城市交通拥堵程度较小，来自含铅汽油的燃烧颗粒也有限。从 20 世纪城市铅污染的时代来看，新斯科舍省的圣约翰市儿童具有小城市的血液铅特征。
