Parental occupational exposure to heavy metals and welding fumes and risk of testicular germ cell tumours in offspring: a registry-based case-control study

Data are scarce on the association between prenatal/preconception environmental exposure and testicular germ cell tumour (TGCT) in offspring. The authors examined parental occupational exposures to heavy metals and welding fumes in relation to TGCT in offspring in a registry-based case-control study (NORD-TEST Study). TGCT cases diagnosed at ages 14-49 years in Finland (1988-2012), Norway (1978-2010), and Sweden (1979-2011) were identified through nationwide cancer registries. These cases were individually matched by country and year of birth to controls selected from population registries. Information on parental occupations was retrieved from censuses. From this, the authors estimated prenatal/preconception exposures of chromium, iron, nickel, lead, and welding fumes (all three countries), and cadmium (Finland only) for each parent using job-exposure matrices specifying prevalence (P) and mean exposure level (L). Exposure indices were calculated as product of P and L (P×L), and exposure categories were based on P×L or different combinations of P and L. The study comprised 8,112 cases and 26,264 controls. A statistically non-significant elevated risk of TGCT was observed where P×L>0 except for paternal exposure to cadmium. No statistically significant dose-response relationship was found, but a statistically significant elevated TGCT risk associated with paternal exposure category where both P and L of chromium were high (vs. no chromium; odds ratio=1.37, 95% confidence interval; 1.05-1.79). The authors concluded that the findings from the study provide little evidence of associations between parental exposures to heavy metals/welding fumes and TGCT in offspring with the potential exception of high paternal chromium exposure. Further research on paternal chromium exposure is warranted.

Authors: Togawa K, Le Cornet C, Feychting M, Tynes T, Pukkala E, Hansen J, Olsson A, Oksbjerg Dalton S, Nordby KC, Uuksulainen S, Wiebert P, Woldbæk T, Skakkebæk NE, Fervers B, Schuz J. ;Full Source: Cancer, Epidemiology, Biomarkers & Prevention. 2016 Jul 20. pii: cebp.0328.2016. [Epub ahead of print] ;