Hryhorczuk Daniel, Persky Victoria, Piorkowski Julie, Davis Jennifer, Moomey C Michael, Krantz Anne, Runkle Ken D, Saxer Tiffanie, Baughman Thomas, McCann Ken
Great Lakes Center for Children's Environmental Health, John H. Stroger Jr. Hospital of Cook County, Chicago, Illinois 60612, USA.
Environ Health Perspect. 2006 Jun;114(6):848-52. doi: 10.1289/ehp.8401.
Many older homes are equipped with mercury-containing gas regulators that reduce the pressure of natural gas in the mains to the low pressure used in home gas piping. Removal of these regulators can result in elemental mercury spills inside the home. In the summer of 2000, mercury spills were discovered in the basements of several Chicago-area homes after removal of gas regulators by gas company contractors. Subsequent inspections of approximately 361,000 homes by two northern Illinois gas companies showed that 1,363 homes had residential mercury contamination. Urine mercury screening was offered to concerned residents, and results of urine bioassays and indoor mercury air measurements were available for 171 homes. Six of these 171 homes (3.5%) had a cumulative total of nine residents with a urine mercury > or = 10 microg/L. The highest urine mercury concentration observed in a resident was 26 microg/L. Positive bioassays were most strongly associated with mercury air concentrations > 10 microg/m3 on the first floor [odds ratio (OR) = 21.4 ; 95% confidence interval (CI) , 3.6-125.9] rather than in the basement (OR = 3.0 ; 95% CI, 0.3-26) , and first-floor air samples were more predictive of positive bioassays than were basement samples. Overall, the risk of residential mercury contamination after gas regulator removal ranged from 0.9/1,000 to 4.3/1,000 homes, depending on the gas company, although the risk was considerably higher (20 of 120 homes, 16.7%) for one of the contractors performing removal work for one of the gas companies. Gas companies, their contractors, and residents should be aware of these risks and should take appropriate actions to prevent these spills from occurring and remediate them if they occur.
许多老式房屋都配备了含汞气体调节器，这些调节器可将主管道中的天然气压力降至家用燃气管道所使用的低压。移除这些调节器可能会导致室内出现元素汞泄漏。2000年夏天，天然气公司承包商移除气体调节器后，在芝加哥地区几所房屋的地下室发现了汞泄漏。随后，伊利诺伊州北部的两家天然气公司对约36.1万所房屋进行了检查，结果显示有1363所房屋存在住宅汞污染。为相关居民提供了尿汞筛查，171所房屋提供了尿生物测定结果和室内汞空气测量结果。这171所房屋中有6所（3.5%）共有9名居民尿汞≥10微克/升。居民中观察到的最高尿汞浓度为26微克/升。尿生物测定呈阳性与一楼汞空气浓度>10微克/立方米最为相关[比值比（OR）=21.4；95%置信区间（CI），3.6 - 125.9]，而非地下室（OR = 3.0；95%CI，0.3 - 26），并且一楼空气样本比地下室样本更能预测尿生物测定呈阳性。总体而言，移除气体调节器后住宅汞污染的风险为每1000所房屋0.9至4.3例，具体取决于天然气公司，不过对于为其中一家天然气公司进行移除工作的一名承包商而言，风险要高得多（120所房屋中有20所，16.7%）。天然气公司、其承包商和居民应意识到这些风险，并应采取适当行动防止这些泄漏发生，一旦发生应进行补救。
