Rapid and sustainable detoxication of airborne pollutants by broccoli sprout beverage: results of a randomized clinical trial in China.
Level 2 - randomized trial
Individual randomized controlled trial
PubMed 24913818 · doi:10.1158/1940-6207.CAPR-14-0103
What was done
A 12-week randomized clinical trial enrolled 291 adults from rural Qidong in the Yangtze River delta region of China, an area with high levels of airborne pollution. Participants received either a placebo or a daily broccoli sprout-derived beverage delivering 600 µmol glucoraphanin and 40 µmol sulforaphane. Urinary excretion of glutathione-derived mercapturic acid conjugates of benzene, acrolein, and crotonaldehyde, along with sulforaphane metabolites, was quantified before and throughout the intervention using liquid chromatography-tandem mass spectrometry.
What was found
Compared with placebo, participants receiving the broccoli sprout beverage showed rapid and sustained increases in urinary excretion of conjugates for benzene (61% increase, P ≤ 0.01) and acrolein (23% increase, P ≤ 0.01). No significant difference was observed for crotonaldehyde excretion. Higher baseline benzene mercapturic acid excretion occurred in GSTT1-positive individuals relative to the GSTT1-null genotype across study arms. Urinary sulforaphane excretion indicated stable bioavailability across the entire 12-week intervention.
Why it matters
This trial demonstrates that dietary glucoraphanin and sulforaphane can sustainably enhance the excretion of volatile airborne carcinogens and toxicants in humans. It suggests a low-cost nutritional strategy to augment endogenous detoxification pathways in heavily polluted environments.
Limits
The study evaluated urinary clearance biomarkers rather than clinical health outcomes (such as cardiopulmonary disease or cancer incidence). Findings from this rural Chinese cohort with high environmental exposure may not directly generalize to populations with lower baseline pollutant levels. The intervention had no detectable effect on crotonaldehyde excretion.