Levels of persistent organic pollutants in human milk in two Chinese coastal cities, Tianjin and Yantai: Influence of fish consumption

Abstract

In 2006–2007, we collected human milk from 60 and 48 donors in the Chinese coastal cities of Tianjin and Yantai, respectively, in accordance with the WHO/UNEP global milk survey. We determined the concentrations of organochlorine pesticides by GC/MS/MS and dioxins by XDS-CALUX bioassay in the individual milk specimens. The geometric mean concentrations (GMs) of β-HCH (586.7ng g−1 fat), total DDTs (855.9ngg−1 fat), and dl-PCBs (4.4pg CALUX-TEQg−1 fat) in the milk from Yantai were higher than those from Tianjin (254.4ng g-1 fat, 654.7ngg−1 fat, 1.9pg CALUX-TEQ g−1 fat, respectively). However, the GMs of HCB (41.1ngg−1 fat) and PCDD/Fs (13.1pg CALUX-TEQg−1 fat) from Tianjin were higher than those from Yantai (15.7ng g−1 fat, 9.9pg CALUX-TEQ g−1 fat). The low ratios of DDT/(DDE+DDD) in milk from both areas suggested that past exposure contributed to the total DDTs body burden. The dl-PCBs body burden in the high sea fish intake group was higher than that in the low intake group, both with and without adjustments for potential influencing factors. For β-HCH, a marginal P value (P=0.063) was observed between high and low sea fish consumption groups after adjusting for potential influencing factors. Donors in the high freshwater fish group showed higher PCDD/Fs and HCB levels than those in the low intake group, both with and without adjustments. Further monitoring studies of POPs contamination in human milk and foods are needed in China.