Importance of Detecting heavy metals in human umbilical cord in Sri Lanka.

Heavy metal contamination in vegetables is a major concern in determining food safety, quality and understanding adverse health impacts. Since early 90’s heavy metal poisoning is becoming a crucial problem in Sri Lankan populations which represents a major national cost waste due to both patient suffering and economic burden. The marketed vegetables are not surely confirmed that they are free from heavy metals. Several studies have shown that leafy vegetables are the heaviest metal contaminated plant. To ensure the quality of the vegetables, various techniques can be used to identify the presence of toxic elements in the vegetables.

Figure 01 — Human exposure of heavy metals https://www.researchgate.net/publication/322655533_Human_Health_Risk_Assessment_for_Inhabitants_of_Four_Towns_of_Rajshahi_Bangladesh_due_to_Arsenic_Cadmium_and_Lead_Exposure/figures?lo=1

The prediction of the effect of heavy metals accumulation and contamination in Sri Lanka is very challenging for the reviewers due to lack of data and infrastructure. Several scientists in Sri Lanka expected to conduct with an aim to determine the heavy metals (Cadmium, Mercury and Lead) accumulation potential of some of the commonly consumed vegetables in Sri Lanka like tomatoes, beetroot, carrot and leafy vegetables such as Kan kun and Gotukola.

Simultaneously the levels of above heavy metals in human umbilical cord blood should study to observe the concentration of accumulated heavy metals to which neonates are exposed. The bio-concentration of metals and dietary daily intake of metals through vegetables for adults has also been considered in this study. as human health is directly affected by consumption of vegetables.

We can use the data and results obtain from these researches to educate the farmers of Sri Lanka regarding the serious consequences of using heavy metal contaminated waterbodies, lands for cultivation purposes. To evaluate the health risk related with these metals, biomonitoring of contamination of heavy metals in different vegetables and the establishment of some recommendations on human diet foodstuff is needed in order to assure a significant improvement in food safety.

There are many pollutant-related medical issues reported in Sri Lanka due to heavy metals and metalloids, including lead (Pb), cadmium (Cd) and mercury (Hg). Due to potential neural and liver toxicity, bone aggregation and inhibition of vital physiological functions, heavy metals are highly toxic. If the heavy metal exposure happens during organogenesis on infants, irreversible structural and anatomical changes may be caused by heavy metals. The below figure 01 shows the face malformations in kids due to heavy metal exposures in prenatal stages.

Figure 02 — Heavy metal exposure of placenta (Image available at https://www.researchgate.net/publication/253335417_Heavy_metals_and_placental_fetal-maternal_barrier_A_mini-review_on_the_major_concerns/)

The placenta works as a shield to block the transmission of infectious substances that protects the embryo and fetus from toxic exposure. However, strong metals do reach the placenta. As an example, Pb and Hg will quickly cross the placenta and accumulate in the tissues of the fetus, while Cd can partially cross. There is no evidence available on the impact of prenatal heavy metal toxicity and trace elements on adverse pregnancy outcomes in the population of Sri Lanka. The placenta and the fetal blood-brain barrier are quickly breached by lead and methylmercury and can impact cognitive development irreversibly. Spontaneous abortions, congenital malformations, decreased birth weight and length, gestational hypertension or impaired neurodevelopment may also be triggered by lead exposure. Pregnancy-induced hypertension, low birth weight and birth defects have been associated with occupational mercury exposure. Because of its potential impact on fetal health, cadmium toxicity is also of great concern. This metal can also be present in cord blood and has been related to reduced birth weight, premature delivery and altered newborn thyroid hormone status. Hence by sampling umbilical cord blood could investigate the status of heavy metals and trace element level in the Sri Lankan community. We can evaluate the impact of heavy metals and trace minerals in the Sri Lankan populations by investigating umbilical cord blood. These kind of studies gives comprehensive understanding of the connections between prenatal exposures and heavy metals.

Several research in clinical diagnostics area demonstrated insightful baseline biomonitoring evidence and shows that in non-occupationally exposed Sri Lankan mothers and their newborns, significant exposure to heavy metals may threaten the health of both. Heavy metal concentrations of the umbilical cord blood can analyze by Atomic Absorption Spectroscopy, and Inductively Coupled Plasma Mass Spectrometry which are the commonly used methods worldwide. To investigate factors such as the environment, diet, lifestyle and/or cultural behaviors that lead to maternal and fetal exposure, more study is also desperately required. Preventive steps should be launched to remove or reduce the excessive risk of prenatal exposure during pregnancy to heavy metals or other toxins until these causes are known.

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