Barium exposure of an invasive breast cancer cluster investigation – quantitative drinking water chemistry for carcinogen search

Quantitative review of oral barium exposure was conducted using drinking water metals data from the confirmed sixfold (18-fold15–39 years) Brisbane Australia invasive breast cancer cluster (IBC) investigation, which also included fivefold duct carcinoma in situ (DCIS). Methods: The new approach herewas to assess sub-guideline on-site water system barium fluctuations and use cancer slope factor (CSF) firstly to profile match barium as a carcinogen, then correlate risk. Results: Dissolved barium was converting, up to 71%, into non-dissolved forms in the cluster location; with only up to 3% in a comparison location. A CSF of approximately 330 (mg L ) 1 gave a chemistrybased number of women of 12, consistent with 14 originally (mostly IBC), less 2 per general population biostatistics. The comparison location gave null women numbers. One-woman IBC correlated to 0.0018 mg/L barium, comparable to the US Environmental Protection Agency’s (USEPA) 0.002 mg/L, 10 4 cancer risk for arsenic. The twoto fivefold San Diego USA IBC cluster had barium as the only metal in common with Brisbane; and, breast cancer alcohol risk factor fingered barium qualitatively. Conclusions: It is put that barium causes IBC and DCIS; proof submitted hereby to wider scrutiny. The relevant barium exposure was likely calcium coprecipitated.