As expected, violation of the 3.8 % safety guideline was related to the high proportion of anaemia in the cohort: 91.4 % (609/666) and 27.6 % (184/666) of children had anaemia and severe anaemia, respectively, with lowest Hb in children aged 6–24 months and 2–6 years (Fig. 2). The gene discussed is GSTM1; the disease is anemia (phenotype).