Exposure to biofuel doubles the risk of lung cancer in women, finds a systematic review that provided risk estimates for the 2010 Global Burden of Disease study.

The analysis of 14 studies found the odds ratios (ORs) for lung cancer risk with biomass for cooking and/or heating were OR 1.17 (95% CI 1.01 to 1.37) overall, and 1.15 (95% CI 0.97 to 1.37) for cooking only.

For studies with adequate adjustment and a clean reference category the ORs were 1.21 (95% CI 1.05 to 1.39) for men (two reports, compiling five studies) and 1.95 (95% CI 1.16 to 3.27) for women (five reports, compiling eight studies).

“Taken as a whole, this review provides stronger evidence than was previously available on the association between household use of biomass fuel for cooking and the risk of lung cancer” the researchers concluded in Thorax.

Around 2.4 billion people worldwide rely on biomass fuels in the home for cooking and heating, so the findings have important implications for public health, they added.