Nitrates significantly impact human health and the environment. Drinking water and vegetables are considered the main sources of exposure to exogenous nitrates for humans. This study aimed to estimate and assess the health hazards from nitrate contamination present in drinking water and vegetables for infants in the north of the Gaza Strip. A total of 252 samples were collected from groundwater and drinking water, and 15 vegetable samples were analyzed with a spectrophotometer. In addition, an ELISA kit was used to determine methemoglobin in 87 infant blood samples. According to the findings of this study, the nitrate concentration in groundwater was in the range from 58.3 mg/L to 178.4 mg/L. Meanwhile, the nitrate levels in drinking water were found to be between 10 and 17 mg/L. As for vegetables, carrots (237.20 ± 53.23 mg kg⁻¹), potatoes (246.80 ± 81.42 mg kg⁻¹), and zucchini (275.86 ± 58.87 mg kg⁻¹) had varying nitrate concentrations. Lastly, the study revealed that methemoglobinemia was present in 32.2% of infant samples in the study area. This study concluded that 97% of groundwater in desalination plants exceeded WHO guidelines (>50 mg/L), and the values of nitrates in drinking water showed the existence of nitrate contamination. Among vegetables, zucchini has the highest nitrate content. Exposure to drinking water and vegetables contaminated with nitrate increased the percentage of methemoglobin levels in infants.

β-thalassemia minor (BTM) and iron deficiency (ID) are common disorders characterized by microcytosis and/or hypochromasia, leading to a challenge in their discrimination during mass-screening programs especially in developing countries where resources are limited. It has been shown with varying reliability that quick exclusion of either disorder could be achieved mathematically using RBC-based indices and formulas. However, none of these proposed indices and formulas considered the sex-based hematological differences. This comparative retrospective study examined the efficacy of using sex-based RBC indices in the mathematical discrimination BTM and ID in adult males and females. The CBC of randomly selected eight hundred adults diagnosed with BTM or ID (200M & 200F BTM, and 200M & 200F ID) were used in the comparisons. The discrimination power, in terms of sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and Youden index were calculated for all subjects and separately for males and females for 20 mathematical indices and formulas. Data revealed significant differences in the RBC-based indices between males and females for both BTM and ID groups. Significant variation in reliability indicators for the different indices and formulas were discovered between males and females samples. Sex-based indices and formulas are necessary to improve the reliability in mathematically discriminating between BTM and ID in mass screening programs. We also advocate for a large-scale multicenter study to establish the parameters of such indices and formulas with sex and age.