US researchers have highlighted a connection between cadmium exposure and impaired contrast sensitivity.
Writing in JAMA Ophthalmology, scientists described their findings from an observational study of 1983 participants from the Beaver Dam Offspring Study.
Over the 10-year period of the study, around one in four study participants developed a contrast sensitivity impairment.
Exposure to cadmium, but not lead, was associated with an increased risk of reduced contrast sensitivity.
Cadmium exposure typically happens through inhaling cigarette smoke and eating green leafy vegetables, rice and shellfish.
The authors concluded that changes in modifiable factors, including cadmium exposure and smoking, could potentially reduce the burden of contrast sensitivity impairment on the population.