Differences in mirex [dechlorane] and dechlorane plus [syn- and anti-] concentrations observed in Canadian human milk. (March 2023)

• Record Type: Journal Article
• Authors: Rawn, Dorothea F.K.; Quade, Sue C.; Corrigan, Catherine; Ménard, Cathie; Sun, Wing-Fung; Breton, François; Arbuckle, Tye E.; Fraser, William D.
• Is Part Of: Chemosphere. Volume 316(2023)
• Publication Date: 2023-03
• Subjects: Human milk -- Chlorinated compounds -- Gas chromatography-high resolution mass spectrometry -- GC-MS; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2023.137784
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: As part of the pan-Canadian Maternal-Infant Research on Environmental Chemicals (MIREC) study, human milk samples were collected between 2008 and 2011, and analyzed for mirex, an organochlorine insecticide and flame retardant, in addition to dechlorane plus ( syn - and anti -DDC-CO), the flame retardant replacement for mirex. Mirex was analyzed separately, using a method for the analysis of existing organochlorine insecticides, while the presence of DDC-CO isomers was determined using a method developed for the detection of emerging flame retardants. Mirex was detected in all samples analyzed (n = 298), while syn - and anti -DDC-CO were present in 61.0% and 79.5% of the samples, respectively (n = 541). Mirex concentrations have declined in human milk since the 1990s. Since this is the first pan-Canadian dataset reporting DDC-CO concentrations in human milk, no temporal comparisons can be made. Maternal age was correlated with concentrations of both compounds although parity did not impact concentrations of either analyte. Given the presence of this relatively recently identified flame retardant (DDC-CO) in human milk from women across Canada, studies to identify dominant sources of this compound are critical. Despite low concentrations of environmental chemicals in human milk from Canadian women, Health Canada supports breastfeeding of infants because of the important health benefits to both the mothers and their infants. Graphical abstract: Image 1 Highlights: First national study of dechlorane plus in Canadian human milk. Higher detection frequency for anti -dechlorane plus than syn -dechlorane plus. Mirex was detected in 100% of the samples analyzed, a decrease in levels observed. Higher concentrations of mirex were observed than syn - and anti -dechlorane plus. Age was correlated with both mirex and ΣDDC-CO concentrations, but parity was not.