Food safety

Illness induced by unsafe food is a problem of great public health significance. This study relates exclusively to the occurrence of chemical agents which will result in food unsafe for human consumption since the matter of food safety is of paramount importance in the mission and operation of the manned spacecraft program of the National Aeronautics and Space Administration

Evaluation and Heavy Metal Concentration Assessment in Selected Brands of Infant and Toddler Food Types in Houston, Texas

Heavy metals and metalloids such as lead, cadmium, arsenic, nickel and zinc are an unavoidable contaminant of our ecosystem because of its natural occurrence They are also introduced into the environment anthropogenically through manufacturing, industrial agricultural processes which contaminates the food chain when taken up by food producing crops as a result of their presence in soil and water used in planting or feeding livestock. The adverse effects of these toxic elements have become a global threat to food security, particularly due to their inextricable association with human health. Exposure to environmental contaminants from daily diet is a major concern for all ages, although children are more vulnerable to their effects because they consume more food relative to their body weight and have underdeveloped nervous system. Exposure to toxic metals in children presents long-term health risks to growing infants and toddlers and have been linked but not limited to a variety of health issues such as disruptive behavior, neurological damage and attention deficit hyperactivity. A report recently released by the U.S House of Representatives in 2021, raised concerns about the dangerously elevated levels of heavy metals in baby food due to improper testing of raw ingredients used in making baby foods and finished baby food products and under-reporting by food manufacturers, of these high levels of toxicity which keeps toxic products on the market. Although, heavy metals can be found in some foods due to contaminated water and soil, their levels in foods, especially baby foods should be of great concern. The U.S. Food and Drug Administration (FDA) has proposed daily permissible limits for some of these metals; however, a major challenge to this remains subpar testing practices, lenient self-regulating standards set by different food manufacturers where there are inconsistent and conflicting tolerable safe limit values set by various food agencies. The new U.S. FDA initiative, known as Closer to Zero Plan (C2Z) seeks to reduce to almost zero level, the toxic element exposures from foods eaten by babies and young children, therefore, this study was aimed at evaluating heavy metal concentrations in baby and toddler food products targeted at infant and toddler age groups produced by leading brands indicated in the report. Ten commercial baby foods from the top seven leading brands in the United States were purchased from a local store, representing six ingredient categories listed as a diary, fruit; leguminous vegetable; beef, chicken, root vegetable; or grains and evaluated for arsenic (As), cadmium (Cd), Zinc (Zn) lead (Pb), Nickel (Ni), aluminum (Al) and chromium (Cr) in triplicates for heavy metal concentrations using the triple quadrupole inductively coupled mass spectrometry ) QQQ_ICP-MS), a tandem mass spectrometer method that has the capability of detecting analytes at lower detection limits. Nickel, Chromium and Zinc are vital in living organisms and necessary for metabolic and immune support while Arsenic, and Lead are non-essential but can be highly toxic even at extremely low concentrations of 0.005ug/g. In all the food types evaluated, aluminum (4.09 µg/g and 2.50 µg/g) and zinc (33.5 µg/g 69.5 µg/g, and 30.2 µg/g) were the most elevated in the infant food age group while lead and cadmium metals in all other food types were observed at levels not exceeding the tolerable limits except in rice cereal. The acceptable daily limits of Aluminum and Zinc are 1 µg/g /day and 0.3 µg/g /day. The mixed model generated for this analysis found significant differences in metal concentrations (F6,24=2.75, p=0.03). The overall average metal concentration in the food was 0.96 µg/g. No significant correlations were found between the packaging materials used and the observed metal concentrations (P \u3e0.05, Std error 1.94). Food products formulated from fruits and root tubers commonly referred to as plant-based food products, exhibited the highest concentrations of all tested heavy metals although none of the food labels reported the levels of heavy metal concentrations in the food products. Transparency in reporting toxic metal content on food labels will help consumers make an informed decision when purchasing these food products

Heavy Metal Levels in Paddy Soils and Rice (Oryza sativa (L)) from Wetlands of Lake Victoria Basin, Tanzania

A survey of paddy fields in Lake Victoria Basin (LVB) wetlands was conducted at a wider scale in different locations including closer to mining and within urbanized areas in Tanzania. The objective of the study was mainly to assess the present situation with regard to levels of heavy metals in O. sativa grains harvested locally as well as to set the baseline levels of some heavy metals in paddy fields. The results showed that the levels of Cadmium, Chromium, Copper, Lead, Zinc and total Mercury in brown rice are generally within the acceptable levels for human food. However, higher concentration of Hg was found in the husks, suggesting the significance of atmospheric dispersal of Hg in the basin. It is also worthwhile noting that all the sampled paddy fields in LVB have heavy metal concentrations within limits for production of safe rice for human consumption.Keywords: Wetlands; Lake Victoria Basin; Heavy metals; Paddy soil; RiceTanz. J. Sci. Vol 36 2010, 59-7

SPATIAL ANALYSIS OF EXPOSURE TO SOIL HEAVY METALS, ORAL BIOACCESSIBILITY AND RISK ASSESSMENT IN HOUSTON, TEXAS

Chronic exposure to heavy metals could lead to adverse health effects such as cancer, neurological development diseases and immunological diseases. The ingestion pathway has been considered the major exposure route for heavy metal contaminated soils. Heavy metals may be proportionally bioaccessible for the human body to absorb. There are no risk assessment studies done in Houston to evaluate health risks from exposure to heavy metals and no spatial analysis done yet. The aims of this dissertation are (1) to characterize 13 heavy metals: magnesium (Mg), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), lead (Pb), barium (Ba), and cadmium (Cd) in soils in Houston, Texas (TX), and evaluate spatial distribution maps of these metals; (2) to assess bioaccessibility of 13 metals (Pb, Cd, Cu, As, Cr, Zn, Ni, Mn, Ba, Co, Mg, Fe, and V) in soils; (3) to estimate human health risks of 10 toxic metals (As, Ba, Cd, Cr, Cu, Mn, Ni, Pb, Zn, and V) using metal concentrations in soils and bioaccessibility concentrations, and to simulate cancer and non-cancer risks maps. We sampled top soils at 96 locations in Houston, TX. We used microwaved-acid digestion system to prepare the soil samples and analyzed metal concentrations in soils by inductively coupled plasma mass spectrometry. Besides, we obtained Environmental Justice Screening and Mapping Tool Indexes to identify possible high exposure groups and emission sources of metals. We simulated heavy metal distribution by ordinary kriging in SAS software and ArcGIS software. Moreover, we used an in-vitro bioaccessibility method to obtain percent bioaccessibility fractions (%BAF) in gastric phase and gastro-intestinal phase. We assessed human health risks by using metal concentrations in soils and bioaccessibility results among five age groups, 0 to \u3c 1 year old (infants), 1 to \u3c 6 year old (toddlers), 6 to \u3c 12 years old (children), 12 to \u3c 18 years old (teenagers), and 18 to \u3c 78 years old (adults), and estimated hazard index (HI) and cancer risks with SAS software and ArcGIS software for non-sampled area. Ninety-six percent of samples had either one or more than one metal over Texas Commission on Environmental Quality (TCEQ) background values. Pb and Zn had more than 80% of samples over TCEQ background levels. We found that closer proximity to National Priority sites and Risk Management Plan sites had higher Ni, Cr, Ba, Cu, Pb and Zn in soils than further proximity. We also discovered environmental justice issues in Houston as minority and low income groups live in neighborhoods with high Ni, Cr, Ba, Cu, and Zn concentrations in soils. We found that most of the metals had decreasing %BAF from gastric phase to gastro-intestinal phase, except Cu and V. The %BAF in gastric phase ranged from 1.22 % to 69.71 %. The %BAF in gastro-intestinal phase ranged from 0.22 % to 45.87%. For chronic non-cancer health effects, all hazard indexes among 5 age groups were under one (1). The infants group had the highest HI followed by toddlers group. Pb contributing 90% and As contributing 6% in HI when applying all three experimental results. Adults group’s cancer risks were 1.02 in a million followed by toddlers group. We suggested that future metal pollution studies interested to point sources in Houston should focus in East and South side. Other studies interested to traffic volume should have better study design to differentiate emission since Houston doesn’t have zoning between industrial area and residential area. Furthermore, for exposure of young children, future studies should focus for soils in playgrounds, parks, or schools, especially around old downtown areas

Compiled data on the vascular aquatic plant program, 1975 - 1977

The performance of a single cell, facultative sewage lagoon was significantly improved with the introduction of vascular aquatic plants. Water hyacinth (Eichhornia crassipes) was the dominant plant from April to November; duckweed (Lemna spp.) and (Spirodela spp.) flourished from December to March. This 2 ha lagoon received approximately 475 cu m/day of untreated sewage and has a variable COD sub 5 loading rate of 22-30 kg/ha/day. During the first 14 months of operation with aquatic plants, the average influent BOD sub 5 was reduced by 95% from 110 mg/l to an average of 5 mg/l in the effluent. The average influent suspended solids were reduced by 90% from 97 mg/l to 10 mg/l in the effluent. Significant reductions in nitrogen and phosphorus were effected. The monthly kjeldahl nitrogen for influent and effluent averaged 12.0 and 3.4 mg/l, respectively, a reduction of 72%. The total phosphorus was reduced on an average of 56% from 3.7 mg/l influent to 1.6 mg/l effluent

Investigation of toxic chemicals in plant-based milk alternatives

Milk is a dietary component consumed all over the world and is known to be essential for development in children. Despite all the nutritional advantages associated with milk consumption, several issues like lactose intolerance, and high lipid content, etc., negatively affects the perception of cow milk consumption, and has grown into general health concerns. Issues with cow milk consumption drove for a healthier alternative and this led to plant-based milk alternatives (PBMA). Several studies have linked consumption of these PBMAs with other negative effects such as: allergy, poor nutrient profile and the presence of other foreign chemicals. This study’s main objective is to investigate the chemical profile of milk samples to detect the presence of toxic chemicals such as heavy metals and pesticides. As well as detect the concentration of essential elements present in milk samples. This study uses instrumentation analysis such as an inductively coupled plasma mass spectrometry (ICPMS) device to analyze the presence of heavy metals as well as essential elements in milk samples. For organic contaminants which include pesticides, the gas chromatography (GC) with electron capture detector (ECD) is used. Results obtained for heavy metals showed trace concentration of Pb, Cd and Cr in the majority of the PBMA samples, specifically Hemp milk (1.0 µg/l for Pb; 1.2 µg/l for Cr) and Soy milk (0.4 µg/l for Cd), while heavy metal concentration for cow milk was below detection limit. Organochlorine pesticide (OCPs) residue limit was present in all milk samples. The concentrations for the OCPs banned by the Stockholm Convention was higher than the residue limits set by EPA and FAO-WHO. This is of concern as most banned OCPs are classified as carcinogens, even at trace concentrations. HCB, Mirex, toxaphene, and Chlordane had residue concentrations above 200 µg/kg. Overall, cow milk had no significant difference in pesticide residue limits compared to PBMAs like almond, coconut, soy, and oat. Almond, coconut and soy milk were more fortified in essential elements than cow milk. However, heavy metal concentration in cow milk was BDL compared to that of most PBMAs

Elucidating the Effects of Cerium Oxide Nanoparticles and Zinc Oxide Nanoparticles on Arsenic Uptake by Rice (Oryza sativa) in a Hydroponic System

Arsenic (As) is a toxic element widely encountered in the environment and a food safety concern. The use of engineered nanoparticles (ENPs) has grown rapidly due to the unique properties that make them beneficial in a wide range of technologies. Studies abound concerning the phytotoxicity of ENPs and their accumulation in plant tissues. However, investigations on ENPs interactions with co-existing contaminants in a plant system, especially with redox sensitive heavy metals, are rare. Two ENPs of interest are cerium oxide nanoparticles (CeO₂ NPs) and zinc oxide nanoparticles (ZnO NPs). The goals of this study were to: (1) determine the impact of CeO₂ NPs and ZnO NPs on the As accumulation in rice, and (2) evaluate whether inorganic As species including both As(III) and As (V) may modify the plant uptake and accumulation of the metal elements of co-present CeO₂ NPs and ZnO NPs. This was done by administering either 1 mg/L of As(III) or As(V), or 100 mg/L of CeO₂ NPs or ZnO NPs or Zn²⁺, or different combinations of As and ENPs or ions at the same concentrations to rice plants. Rice (Oryza sativa) was utilized in this study as a model plant duo to its high propensity for As uptake, and its widespread consumption as a staple food around the world. A hydroponic system was used to avoid the compounding effects of soil and the microorganisms in soil. The results indicated that CeO₂NPs did not show significant effect on total As plant accumulation. The presence of ZnO NPs and Zn²⁺ significantly reduced total As in rice seedlings, except for the concentration of total As in rice shoots with the co-presence of ZnO NPs and As(III). The co-presence of As significantly increased Ce in rice shoots in the CeO₂ NPs + As(III) treatment but did not affect the plant uptake of Zn from ZnO NPs or Zn²⁺. The results confirmed the active interactions between ENPs and co-existing inorganic As species and the extent to which their interactions depend on the properties of ENPs as well as the initial oxidation state of As