Effect of a clean stove intervention on inflammatory biomarkers in pregnant women in Ibadan, Nigeria: A randomized controlled study

Environ Int. 2017 Jan:98:181-190. doi: 10.1016/j.envint.2016.11.004. Epub 2016 Nov 10.


Background: Exposure to household air pollution (HAP) has been linked to systemic inflammation. We determined the impact of transition from traditional firewood/kerosene stove to bioethanol-burning stove on inflammatory biomarkers in pregnant Nigerian women.

Methods: Women (n=324), cooking with kerosene/firewood, were recruited during their first trimester of pregnancy from June 2013-October 2015 and were randomly allocated to either control (n=162) or intervention (n=162) group using web-based randomization. Controls continued to use their own firewood/kerosene stove, while intervention participants received bioethanol CleanCook stoves. Serum concentrations of retinol-binding protein (RBP), malondialdehyde (MDA), tumor necrosis factor alpha (TNF)-α, interleukin (IL)-6, and IL-8 were measured by ELISA.

Results: After excluding 53 women (loss of follow-up, untimely biomarker assessments, incorrect dates of enrollment), data from 271 women were included in analysis. Mean (SD) change in RBP, MDA, TNF-α, IL-6, and IL-8 between baseline and third trimester was -2.16 (4.47), -19.6 (46.4), 3.72 (37.2), 0.51 (14.4), and 13.2 (197), respectively, in intervention and -2.25 (4.30), -24.6 (43.6), 7.17 (32.6), -1.79, (11.4), and 31.3 (296) in control groups. None of these changes differed significantly between the two treatment arms. However, changes from baseline in TNF-α levels were significantly different between intervention and control groups in subset of women (n=99) using firewood before trial (-7.03 [32.9] vs. +12.4 [33.6]; 95% CI for group difference: -35.4 to -3.4, p=0.018).

Conclusions: Decrease in TNF-α concentration from baseline to third trimesters in intervention group women could indicate reduced cardiovascular stress and prothrombotic effects from decreased HAP. Our findings suggest that ethanol-burning stoves may mitigate cardiovascular health risks.

Keywords: Bio-ethanol; Cleancook stove; Cytokines; Nigeria; Pregnant women; Systemic inflammation.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adolescent
  • Adult
  • Air Pollution
  • Air Pollution, Indoor / adverse effects
  • Air Pollution, Indoor / prevention & control*
  • Biofuels
  • Biomarkers / blood*
  • Cooking / instrumentation*
  • Ethanol
  • Female
  • Household Articles
  • Household Products
  • Humans
  • Inflammation / blood*
  • Inflammation / etiology
  • Interleukin-6
  • Kerosene
  • Nigeria
  • Oxidative Stress*
  • Pregnancy
  • Pregnant Women / ethnology
  • Young Adult


  • Biofuels
  • Biomarkers
  • IL6 protein, human
  • Interleukin-6
  • Kerosene
  • Ethanol