The effects of joint exposures to enviornmental oxioants on methemoglobin formation: Copper/nitrite and copper/chlorite

Abstract

Simultaneous exposure to chemicals which can oxidize hemoglobin to methemoglobin is common. Although the effects of these agents have been extensively documented Individually, little research considers their potential Interactive effects. In vitro experimentation on female Dorset sheep erythrocytes assessed the Interactive capacity of copper and chlorite and copper and nitrite to affect methemoglobin formation. All combinations of doses which produced 1.25, 2.5, 5, 10 and 15 percent methemoglobin and controls were tested. These evaluations therefore, included data on each chemical alone and their respective two‐way combinations. The responses observed were principally additive In nature (the sum of the Individual effects). However, the statistical analysis of the copper and chlorite Joint exposure rejected the addltlvlty hypothesis displaying a modest degree of antagonism.

Key words:

• methemoglobin
• copper
• chlorite
• nitrite
• sheep
• red blood cells
• glucose‐6‐phosphate dehydrogenase deficiency (G‐6‐PD)
• animal model
• risk assessment
• In vitro