Virginia Research Day 2021

MERCURY EXPOSURE AND POTENTIAL RISKS OF RICE BASED INFANT FOODS IN INFANTS: A LITERATURE REVIEW Emily K. Hutcherson, Durga A. Kumar, James R Palmieri, Meghan L. Wilson Edward Via College of Osteopathic Medicine

Mercury & Heavy Metals in Rice

Conclusion

Abstract

Methylmercury (MeHg) is a subset of organic mercury that is found in rice, fish, and rice plants and in run-off waste in water, atmospheric deposition, and in fertilizer [63]. Within the rice-based cereal foods, there is a difference in methylmercury intake [69]. There is also a difference of methylmercury levels in products within different manufacturing countries. Especially in countries such as Argentina and China where environmental conditions are different Outstanding factors ● fish quantity Rice is a common source of dietary heavy metals as the plant has the capability to uptake environmental contaminants[51]. Contaminated rice can be used to make rice-based infant foods which is a common source of nutrition for infants [52-53]. Arsenic is a frequent contaminant in rice-based food due to increased uptake capability compared to other carbs. A Polish study tested infant rice-based foods found ⅔ of samples exceeded pre-determined concentrations of arsenic[57]. Reasons rice-based infant foods have smaller amounts of heavy metals than rice: ● Mixed with whey or other compounds ● Lack of testing Heavy Metals in Infant Foods Neurocognitive: ● Infant exposure to mercury can lead to poor memory, speech delay and worsened academic performance ● Kim et al. discuss that exposure to metals such as lead and mercury can lead to sleep problems in infants [83] ● ADD/ADHD symptoms may be improved in children by eliminating heavy metals from their diet [84] Physical: ● Post-birth weight gain and head circumference were negatively correlated with increased intake of lead and arsenic [97] ● Evidence suggests that nutrients from contaminated food sources outweigh the risk of ingesting the heavy metals [85] ● Pregnant people are able to pass on heavy metals to baby in-utero as well as postnatally during breastfeeding [87, 89] The effect of Mercury and Heavy Metals on Childhood development ● Arsenic → accumulates in soil of rice paddies from mining and its associated waste disposal [35-36] ● Lead → Rice paddies in areas of high traffic allows for translocation of lead into the rice grain [18, 41] ● Cadmium → easily absorbed into the leaves of the rice plant and mobilized to the grain [42, 45, 47] ● Mercury → microbial methylation of inorganic mercury that naturally occurs in soil Teething Biscuits Rice baby Cereal 0.0066 mcg 0.0092 mcg ● organic processing ● gluten-free foods Mercury in Rice-based infant foods Central and East Asia produce 90% of the world’s rice. Rice paddies in these countries are frequently around areas of heavy traffic, metal mines and coal burning power plants, making the crops susceptible to harmful wastes and pollutants.

As a primary source of carbohydrates after breastfeeding and formula, infants are given rice- based cereals and snacks. These snacks could potentially have mercury and other heavy metal contaminants that could lead to neurological, physical and cognitive developmental issues. Much of the research discussed has shown that there are heavy metal contaminants in rice plants and rice- based infant foods. As well as studies showcasing the long-term effects of heavy metal poisoning in infant. Additional studies are needed in order to evaluate the amount of mercury in rice-based infant foods and if it is found at higher concentrations in certain brands or in organic food compared to regular products. 1. Analysis of mercury and heavy metals in popular brands of organic rice-based infant foods 2. Analysis of mercury levels in different types of rice-based infant foods 3. An analysis of mercury levels in rice-based infant foods based on the geographical region where the rice is grown 4. Determination of which infant cereal brands currently on the market have the highest concentration of Hg and determine the primary source of Hg Future Studies A special thank you to Drs. Palmieri and Wilson for helping guide and edit this literature review. Acknowledgements Screening of rice-based infant products Monitoring rice growth environments

Rice-based infant cereals and snacks are popular starter and weaning foods for infants around the world. Recent research has indicated that rice can accumulate a variety of heavy metals, with mercury posing the biggest risk to human health. During manufacturing and processing of infant foods, these heavy metals are not removed, thus causing increased incidence of exposure. Mercury and heavy metal exposure in infants is significantly more detrimental than in adults and can cause physical and neurocognitive developmental defects. This literature review evaluated 97 sources found through PubMed and Google Scholar to determine the prevalence of mercury and heavy metals in rice-based infant foods. In conclusion, multiple studies showed the continued presence of these contaminants in rice-based infant foods along with how exposure can cause long term side effects in infants. Further studies are warranted to evaluate mercury levels in certain brands of infant foods and to determine if there is a statistically significant difference in mercury levels of organic vs. non-organic infant foods. . We review the occurrences of heavy metals in rice- based infant foods. Heavy metals discussed include arsenic (As), lead (Pb), cadmium (Cd) , copper (Cu), mercury (Hg) and zinc (Zn). Heavy metals are consistently found in rice plants as heavy metal compounds are easily transported through soil, atmosphere, and irrigation systems [1-4]. Rice is frequently consumed as a carb source and acts as a transitional meal for infants [5]. When rice is processed into rice-based infant food, heavy metals within the rice grains can be transferred into the infant food and cause harmful effects. Negative effects of heavy metal exposure in infancy include: ● Cognitive ● Neurological ● physical developmental delays ● continued problems in their future life. Introduction

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