Metal Interactions in carcinogenesis†

Presented at the Workshop on Carcinogenic and/or Mutagenic Metal Compounds, Geneva, September 12–14, 1983.

Mixed exposures to a number of metallic compounds may give rise to a carcinogenic response in humans.

An interaction between occupational exposure to arsenic and cigarette smoking has been documented epidemiologically. A multiplicative effect was indicated concerning the occurrence of lung cancer when both of the exposures were present. Several experimental studies have been reported in the literature concerning interactions between benzo(a)pyrene and Fe₂O₃ as well as some other metallic compounds like Ni₃S₂, PbO, MgO and TiO₂ in relation to respiratory carcinogenicity. There is also limited evidence of a positive interaction between arsenic trioxide and benzo(a)pyrene. Particles containing V and Ni were obtained from the flue gases of power plants burning heavy fuel oil. Such particles were not carcinogenic themselves but enhanced the carcinogenicity of benzo(a)pyrene even more efficiently than Fe₂O₃.

Increased dietary selenium intakes can decrease the carcinogenicity of several organic carcinogens in animals and dietary zinc can effectuate both enhancement and inhibition of carcinogenicity depending on dietary concentration.

Key Words:

• Arsenic
• antimony
• benzo(a)pyrene
• selenium
• zinc
• smelter workers
• flue gas particles
• smoking habits
• cancer
• interactions
• testes
• respiratory tract

Notes

Presented at the Workshop on Carcinogenic and/or Mutagenic Metal Compounds, Geneva, September 12–14, 1983.