Cyanobacterial toxins, microcystins, have a potent tumor-promoting activity. We investigated the level of microcystins in drinking water collected from 1992 to 1994 in Haimen City, China, where people who drink pond ditch water usually incurred a high incidence rate of hepatocellular carcinoma compared with those who drink well water. High-performance liquid chromatography, liquid chromatography/mass spectrometry (LC/MS), and protein phosphatase inhibition assay (pp assay) were used to identify and quantify the microcystins. Microcystin LR and [D-Asp3]microcystin LR were detected in 2 of 50 samples at a concentration less than 100 ng/L by LC/MS in 1992. Although no microcystins were found by the chemical method in 1993, 6 of 7 samples except for 3 tap water samples showed an approximate amount of 100 ng/L by using the pp assay in 1994. The obtained results supported the epidemiological results reported by Yu.
No takes yet. Share an insight, caveat, or question.
Harada et al. (2006) studied this question.