Oral Reference Dose Research Articles

Assessment of Heavy Metals and Human Health Risk in Pastas Consumed in Makurdi, Benue State

This is investigated heavy metals (Pb, Ni, Cd, Zn, and Cr) bio-concentration and bioaccumulation in Spaghetti consumed in Makurdi, Nigeria. The pasta samples were collected randomly from five markets (Modern, Wurukum, High level, Wadata and North Bank) in Makurdi and analyzed for the heavy metals by the atomic Absorption spectrophotometric technique after acid digestion. some human health risk Parameters: daily dietary Intake (DDI), daily intake of metals (DIM), health risk index (I-IRI), and target hazard quotient ((THQ) were also calculated. Heavy metal risk index (HRI), and target hazard quotient (THQ) were also calculated Heavy metal concentrations (mg/kg) in spaghetti across the markets ranged as Pb (1.52), Ni (3.57), Zn (O.39), Cd (0.40), Cr (19.95). The metal concentrations obtained were above the permissible limits recommended by the WHO/FAO, except Pb which was not detected in four (4)markets Comparing the DIM, DDI, HRI and THQ values with reference oral dose (RfDo), suggested that the consumption of spaghetti is nearly free of risks.(THQ) value of the heavy metal were less than one(l) indicating that there is a relative absence of health risk THQ in all metals is less equal to one (l) Cr which is greater in some of the markets in spaghetti indicating that there is no serious potential health risk. Precautionary measures should be taken to avoid bioaccumulation of these heavy metals. Therefore, it is concluded that these, pasta are partially safe for public consumption as they contain high amount of heavy metals that would constitute danger of metals poisoning.

Associations of gestational exposure to organophosphate esters with thyroid hormones in cord plasma and the safety threshold of exposure in pregnant women.

As a class of synthetic chemicals, organophosphate esters (OPEs) were shown to have thyroid hormones (THs) disrupting potentials in animal studies, while epidemiological evidence on gestational exposure to OPEs and thyroid disruption is limited. Besides, assessment on the safety threshold of OPEs exposure during gestation is especially scarce. Based on the Shanghai Minhang Birth Cohort Study, we measured maternal urine concentration of 8 OPE metabolites and THs levels in cord plasma and examined their associations using multiple linear regression and quantile g-computation (QGC) models. The benchmark dose (BMD) and its lower limit (BMDL) of urine OPE metabolites concentrations were further estimated via the Bayesian Benchmark Dose Analysis System (BBMD) to reflect the safety threshold of exposure in pregnant women. The corresponding daily intake (DI) of BMDL was then calculated and compared with the current oral reference dose (RfD). A total of 309 mother-newborn pairs were included in this study. Gestational bis (2-butoxyethyl) phosphate (BBOEP) exposure was associated with higher total triiodothyronine (TT3), free triiodothyronine (FT3), total thyroxine (TT4), and free thyroxine (FT4) in cord plasma, while bis(1,3-dichloro-2-propyl) phosphate (BDCPP) was observed to be associated with lower TT3 and FT3/FT4 but higher thyroid stimulating hormone (TSH). In addition, sex-specific effects were observed for bis (2-chloroethyl) phosphate (BCEP), which was associated with lower TT3 in cord plasma of female newborns, and lower TT4 and FT4 in male newborns. Similar results were obtained through QGC model and BBOEP was identified as the main contributor to the higher levels of TT3 and FT3. With benchmark response (BMR) of 10% and background response (P0) of 97.5% for both TT3 and FT3, the BMDL10 of urine BBOEP concentration was 0.50μg/L. Further, the corresponding DI of tris (2-butoxyethyl) phosphate (TBOEP), which is the precursor of BBOEP, was 2.53μg/kg BW/d. Our findings suggest associations between gestational exposure to OPEs and altered THs biomarkers. According to the estimated BMD10 (BMDL10) of BBOEP and the corresponding DI, the current RfD of 15μg/kg BW/d for TBOEP may not protect pregnant women and their newborns from thyroid disruption.

Phosphorous flame-retardant concentration in Finnish daycares dust and children’s exposure

Children in daycare centers are exposed to various chemicals present in indoor dust, including organophosphorus flame retardants (OPFRs). This study analyzed OPFR levels in dust from 18 daycare centers in Tampere, Finland, to assess children’s exposure through dust ingestion, inhalation, and dermal absorption. The OPFRs measured included tris(2-chloroisopropyl) phosphate (TCIPP), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), triphenyl phosphate (TPHP), and 2-ethylhexyl diphenyl phosphate (EHDPP). The median concentrations (μg/g) were significantly higher than those reported in similar studies, with TCIPP (265.27), TDCIPP (31.11), TPHP (12.18), and EHDPP (4.24). These elevated levels are possibly due to fire safety regulations in Finland, that have resulted in the extensive use of flame retardants in various materials. The Margin of Exposure (MOE) calculations, which compared total exposure to oral Reference Doses (RfD), indicated that most OPFRs did not pose a significant risk to children, with MOEs generally above 1000. However, TCIPP had the lowest MoE, suggesting a potential health risk at higher exposure levels.

Comparative Seasonal Trends and Potential Health Impacts of Arsenic and Chromium in Surface Water after Adsorption Using Highly Dispersed Fe3O4 Nanoparticles.

Surface water from springs, rivers, and dams is often used as an unconventional drinking water source in rural areas where potable water is often unavailable. However, this practice carries significant health risks due to potential contaminants. In this study, the concentrations of arsenic (As) and chromium (Cr) were assessed seasonally using graphite furnace atomic absorption spectrometry (GFAAS). Highly dispersed Fe3O4 nanoparticles were synthesized, characterized, and utilized as adsorbents to remove As and Cr ions from various water matrices. The removal process was optimized by adjusting the mass of the nanoparticles, pH levels, and sonication time. To further understand the adsorption process, adsorption isotherms and kinetics were conducted. Physicochemical properties such as pH, electrical conductivity, and total dissolved solids were seasonally evaluated. The average As concentrations were in the range of 13.3-46.8µg/L, while Cr was in the range of 1.02-5.04µg/L. Expectedly, higher concentrations of As and Cr were observed in summer when there was intense precipitation, and the lowest concentrations were observed in winter, with little to no precipitation. The calibrated GFAAS displayed an excellent limit of detection, limit of quantification, and linearity of 0.092-0.13, 0.27-0.34, and 0.27-70µg/L for As, while 0.031-0.07, 0.16-0.21, and 0.16-70µg/L were attained for Cr, respectively. Arsenic levels exceeded 10µg/L in all seasons, indicating that these concentrations were above the maximum permitted levels set by the World Health Organization and the South African National Standards. According to the health risk assessment, high As concentrations were alarming, as they were seasonally increasing, with the chronic daily intake exceeding the oral reference dose, whilst the incremental lifetime cancer risk was significantly high.

Evaluation of potential human health risks associated with Li and their relationship with Na, K, Mg, and Ca in Romania's nationwide drinking water.

Increasing lithium (Li) demand worldwide due to its properties and role in renewable energy will raise water reservoir pollution and side effects on human health. Divergent results regarding Li concentration in water and affective disorders are found in the literature, which is why regional reports are expected. The present study evaluated the occurrence and human health risks resulting from oral exposure, respectively, and the relationship between alkali metals (Li, Na, and K) and minerals (Mg, Ca) in balanced purified water (bottled) and spring water. The ICP-MS technique was used to measure a national database with 53 bottled and 42 spring water samples randomly selected. One-way ANOVA, Pearson correlation, and HCA analysis were applied to assess the possible relationship between metals in water. The possible side effects of Li poisoning of water resources on human health have been evaluated using the Estimated Daily Intake Index (EDI) and Total Hazard Quotient (THQ). The toxic metals (As, Hg, and Pb) were measured, and the results indicate values above the detection limit of 22.3% of samples in the case of lead but not exceeding the safety limits. Depending on the water sources, such as bottled and spring water, the Li concentration varied between 0.06-1,557 and 0.09-984% μg/L. We found a strong positive correlation between Li and Na and Mg, varying between bottled and spring waters (p% <%0.001). Li exceeded the limit set by the Health-Based Screening Level (HBSL) in 41.37 and 19% of bottled and spring water samples. The oral reference doses (p-RfDs) for the noncancer assessment of daily oral exposure effects for a human lifetime exceeded threshold values. The THQ index shows potential adverse health effects, requiring further investigations and remedial actions in 27.58% of approved bottled waters and 2.38% of spring waters. We can conclude that water is safe based on the Li concentration found in drinking water and supported by a gap in strict regulations regarding human Li ingestion. The present study can serve decision-makers and represent a starting database with metals of interest for further clinical studies. Decision-makers can also use it to find solutions for sustainable management of clean and safe drinking water.

Heavy metals accumulation in the meat, kidney and liver of cattle, broilers and goats sold in Quetta, northwestern city of Balochistan, Pakistan

ABSTRACT 1. It was assumed that the concentrations of arsenic (As), chromium (Cr), cobalt (Co), lead (Pb), manganese (Mn) and mercury (Hg) in the meat, kidney and liver of cattle, broilers and goats within Quetta city potentially exceeded the permissible limits for heavy metal content. Risk assessment of these heavy metals on human health were estimated based on daily intake (EDI), target hazard quotient (THQ) and hazard index (HI). 2. Samples of the meat, liver and kidney of cattle, broilers and goats were collected from butcher shops and slaughterhouses in 20 different areas of Quetta city. Overall, 180 samples were analysed, each for six heavy metals. After acid digestion of meat samples, heavy metals analysis was carried out via atomic absorption spectroscopy. 3. The results varied in levels depending upon the species and organ type. The average concentrations of As, Pb and Hg were within the established reference limits of the Australia New Zealand Food Authority (ANZFA 2015) and the European Commission (EC, 2006), although some samples exceeded these limits. Compared with the kidney and meat, the liver was the primary tissue for Cr, Pb and Hg bioaccumulation. Metals concentration were mostly within the normal range in samples from cattle and goats, while the Mn concentration was elevated in broilers. 4. The estimated daily intake (EDI) revealed that the intake of As, Co, Pb and Hg was mainly derived from goat and cattle products, whereas broiler samples were more contaminated with Cr and Mn. The EDIs of Cr and Hg in adults exceeded the oral reference dose, referring to potential adverse effects. The EDIs for Co and Mn were low, suggesting that additional intake sources were necessary. Except for As, none of the determined elements had a target hazard quotient (THQ) above 1.

Accurate Prediction of Rat Acute Oral Toxicity and Reference Dose for Thousands of Polycyclic Aromatic Hydrocarbon Derivatives Based on Chemometric QSAR and Machine Learning.

Acute oral toxicity is currently not available for most polycyclic aromatic hydrocarbons (PAHs), especially their derivatives, because it is cost-prohibitive to experimentally determine all of them. Here, quantitative structure-activity relationship (QSAR) models using machine learning (ML) for predicting the toxicity of PAH derivatives were developed, based on oral toxicity data points of 788 individual substances of rats. Both the individual ML algorithm gradient boosting regression trees (GBRT) and the stacking ML algorithm (extreme gradient boosting + GBRT + random forest regression) provided the best prediction results with satisfactory determination coefficients for both cross-validation and the test set. It was found that those PAH derivatives with fewer polar hydrogens, more large-sized atoms, more branches, and lower polarizability have higher toxicity. Software based on the optimal ML-QSAR model was successfully developed to expand the application potential of the developed model, obtaining reliable prediction of pLD50 values and reference doses for 6893 external PAH derivatives. Among these chemicals, 472 were identified as moderately or highly toxic; 10 out of them had clear environment detection or use records. The findings provide valuable insights into the toxicity of PAHs and their derivatives, offering a standard platform for effectively evaluating chemical toxicity using ML-QSAR models.

Bioaccumulated trace element toxicity in commercially harvested bronze whaler sharks (Carcharhinus brachyurus) of South Africa

Shark meat consumption may pose a significant risk to human health as high levels of toxic pollutants bioaccumulate in muscular tissue. Commercial harvest of Carcharhinus brachyurus meat in South Africa is estimated at 100–300 filleted tons per annum. Muscle tissue samples from 41 sharks were collected from the southern and eastern coastlines of South Africa in 2022 and analysed for 10 trace elements and 8 polychlorinated biphenyl congeners. All trace elements were found to be lower than the regulatory maximum limits for human consumption in most samples irrespective of shark length, sex, and sampling region. However, the estimated daily intake for Mercury and Arsenic exceeded the oral reference dose set by international agencies. The meat from this shark may be consumed due to its low toxic potential for human health, however long-term exposure to C. brachyurus meat should be avoided as it could pose detrimental health risks to consumers.

Invasive Round Goby (Neogobius melanostomus) Fish from the Southern Baltic as a Source of Arsenic and Selenium-Food Safety Aspects.

Minimizing human exposure to arsenic (As) and ensuring an adequate dietary intake of selenium (Se) are significant issues in research on food sources. This study measured the content of As and Se in the muscles, gills, liver, and gonads of the fish round goby (Neogobius melanostomus) to assess the benefits and risks associated with their consumption. This was achieved by using dietary reference intake (DRI), estimated daily intake (EDI), target hazard quotient (THQ), and carcinogenic risk (CR). The elements were analyzed by atomic absorption spectrometry. The mean concentrations of As and Se (in μg kg-1 wet weight) were 25.1 and 161.4 in muscle, 58.8 and 367.4 in liver, 47.4 and 635.3 in gonads, and 16.4 and 228.5 in gills, respectively. Arsenic in the muscle portion of fish accounted for up to 0.5% of the DRI, while Se constituted approximately 30% of the DRI. The EDI values were below the reference oral dose (RfD). The THQ were much below the permissible levels (THQ < 1), and the CR were at least within the permissible limit (CR < 10-4). With regard to the As content, round goby muscles can be deemed safe for consumers. They may also be a valuable source of Se in the human diet. However, round goby consumption should be monitored for the proper and safe intake of these elements.

Assessment of human health risk concerning edible plants contamination with toxic elements around functional and derelict mines

Edible plants samples were analysed for non-carcinogenic and carcinogenic human health risks. The elements nickel (Ni), cadmium (Cd), arsenic (As), lead (Pb), chromium (Cr) and mercury (Hg) analysed using atomic absorption spectrophotometer (AAS). The recovery, limit of detection (LOD) and limit of quantification (LOQ) ranged from 75 to 89 %, 0.001–0.003 and 0.003–0.01, respectively. The mean value of Hg (0.34 mg/kg) exceeded the limit of 0.05 mg/kg recommended by World Health Organization (WHO). The estimated daily intake (EDI) of Cd in adults ranged from 7.93 × 10−7 to 1.43 × 10−4 and that of Hg from 0.07 to 1.27 and Cd (0.08 × 10−4) in children. These are below the oral reference doses (RfD). Hazard Quotient (HQ) of Hg in children was 1.92. The elements Hg and As obtained the highest total hazard (THI) index of 2.02 in mango1 and oil palm. Arsenic possessed the highest cancer risk of 4.5 × 10−4 in children and 1.9 × 10−4 in adults. Cancer risk (CR) ranged from low to moderate (10−6-10−4), which is below the limit of 10−3. The total carcinogenic risk (TCR) of the edible plants were above the limit of 10−6. The study identified minimal As and Hg pollution and carcinogenic risks in edible plants.

Occurrence, seasonal variations, and spatial distributions of current-use organoamine pesticides in the atmosphere of Shanghai, China

An increasing trend in pesticide usage requires a better understanding of the occurrence, fate, and exposure risk of current-use organoamine pesticides (CUOAPs) in the atmosphere as the population grows and climate changes. 33 target CUOAPs were measured in 89 atmospheric samples collected in different seasons from Shanghai, including gaseous and particulate phases. The total concentrations of gaseous phase CUOAPs ranged from 407 to 2980 pg/m3, with an average value of 887 ± 426 pg/m3. Conversely, the total concentrations of particulate CUOAPs were found to be one to two orders of magnitude lower than those in the gas phase, with low detection frequencies. Diphenylamine and Molinate were ubiquitous and predominant in the gaseous CUOAPs. The average total concentrations of gaseous CUOAPs were significantly higher in spring than those in winter and autumn seasons. Gaseous CUOAPs concentrations increased from rural to downtown areas during spring, showing different spatial distribution from winter and autumn. A significant correlation was observed between temperature and the presence of Dicloran, Pirimicarb, Diphenylamine, and Acetochlor. Agricultural activities and city pest control may be the main sources of CUOAPs, while meteorological factors including temperature and wind speed also impact the dispersal of these chemicals in the atmosphere. The increased risk of exposure was observed to be higher during the spring season compared to the autumn and winter seasons, aligning with the pattern of heightened utilization of CUOAPs during the planting and growing phases. The daily inhalation exposure of CUOAPs did not exceed the current oral reference dose.

Detection of Heavy Metals in Some Edible Grains Obtained from Two Markets in Bauchi Metropolis, Nigeria

This study investigated the level of heavy metals (Cd, Cr, Cu, Fe, Pb and Zn) in grains sold in Central and Muda Lawal markets in Bauchi. Our objectives include assessing heavy metal concentrations in the grains and evaluating associated health risks. We utilized Atomic Absorption Spectrophotometry following acid digestion of grains to determine heavy metal concentrations. In Central market-sourced crops, the mean concentrations of Cd, Cr, Cu, Fe, Pb, and Zn were 0.06, 0.49, 0.21, 1.16, 0.15, and 0.17mg/kg respectively. Meanwhile, crops from Muda Lawal market exhibited mean concentrations of 0.06, 0.58, 0.17, 1.62, 0.1, and 0.22 mg/kg for Cd, Cr, Cu, Fe, Pb, and Zn, respectively. Cd, Cr, Cu, Pb, and Zn levels were below the permissible limits. However, Fe exceeded permissible limits in small beans, Syria maize, and white guinea corn from Central market, as well as in Syria maize, Pearl millet II, and white guinea corn from Muda Lawal market. The daily intake of Cd, Cu, and Pb from most studied crops exceeded the oral reference dose, posing potential health risks. Conversely, Cr, Fe, and Zn intake levels were within acceptable limits, posing minimal health risks. Hazard quotient and hazard index values were below 1, suggesting that crop consumption is unlikely to pose health risks.

Nano-CeO2 activates physical and chemical defenses of garlic (Allium sativum L.) for reducing antibiotic resistance genes in plant endosphere

The transmission of manure- and wastewater-borne antibiotic-resistant bacteria (ARB) to plants contributes to the proliferation of antimicrobial resistance in agriculture, necessitating effective strategies for preventing the spread of antibiotic resistance genes (ARGs) from ARB in the environment to humans. Nanomaterials are potential candidates for efficiently controlling the dissemination of ARGs. The present study investigated the abundance of ARGs in hydroponically grown garlic (Allium sativum L.) following nano-CeO2 (nCeO2) application. Specifically, root exposure to nCeO2 (1, 2.5, 5, 10 mg L−1, 18 days) reduced ARG abundance in the endosphere of bulbs and leaves. The accumulation of ARGs (cat, tet, and aph(3’)-Ia) in garlic bulbs decreased by 24.2–32.5 % after nCeO2 exposure at 10 mg L−1. Notably, the lignification extent of garlic stem-disc was enhanced by 10 mg L−1 nCeO2, thereby accelerating the formation of an apoplastic barrier to impede the upward transfer of ARG-harboring bacteria to garlic bulbs. Besides, nCeO2 upregulated the gene expression related to alliin biosynthesis and increased allicin content by 15.9–16.2 %, promoting a potent antimicrobial defense for reducing ARG-harboring bacteria. The potential exposure risks associated with ARGs and Ce were evaluated according to the estimated daily intake (EDI). The EDI of ARGs exhibited a decrease exceeding 95 %, while the EDI of Ce remained below the estimated oral reference dose. Consequently, through stimulating physical and chemical defenses, nCeO2 contributed to a reduced EDI of ARGs and Ce, highlighting its potential for controlling ARGs in plant endosphere within the framework of nano-enabled agrotechnology.

Accumulation of potentially toxic elements in fourfinger threadfin (Eleutheronema tetradactylum) and black pomfret (Parastromateus niger) from Selangor, Malaysia.

The accumulation of potentially toxic elements (PTEs) has raised public awareness due to harmful contamination to both human and marine creatures. This study was designed to determine the concentration of copper (Cu), zinc (Zn), cadmium (Cd), and nickel (Ni) in the intestine, kidney, muscle, gill, and liver tissues of local commercial edible fish, fourfinger threadfin (Eleutheronema tetradactylum), and black pomfret (Parastromateus niger) collected from Morib (M) and Kuala Selangor (KS). Among the studied PTEs, Cu and Zn were essential elements to regulate body metabolism with certain dosages required while Cd and Ni were considered as non-essential elements that posed chronic and carcinogenic risk. The concentration of PTEs in fish tissue samples was analyzed using flame atomic absorption spectrometry (F-AAS). By comparing the concentration of PTEs in fish tissues as a bioindicator, the environmental risk of Morib was more serious than Kuala Selangor because both fish species collected from Morib resulted in a higher PTEs concentration. For an average 62kg adult with a fish ingestion rate (FIR) of 0.16kg/person/day in Malaysia, the estimated weekly intake (EWI) of Cd from the consumption of E. tetradactylum (M: 0.0135mg/kg; KS: 0.0134mg/kg) and P. niger (M: 0.0140mg/kg; KS: 0.0132mg/kg) had exceeded the provisional tolerable weekly intake (Cd: 0.007mg/kg) established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and oral reference dose (ORD) values of Cd (0.001mg/kg/day) as provided by the United States Environmental Protection Agency (USEPA) regional screening level, thus it posed chronic risks for daily basis consumption. Besides, the value of the carcinogenic risk of Cd (0.7-3 to 0.8-3) and Ni (0.5-3 to 0.6-3) were in between the acceptable range (10-6 to 10-4) of the health index that indicates a relatively low possibility cancer occurrence to the consumers in both Morib and Kuala Selangor. This study recommended FIR to be 0.80kg/person/day to reduce the possibility of posing chronic and carcinogenic risks while at the same time obtaining the essential nutrients from the fish.

Dietary exposure levels to polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and non-ortho-polychlorinated biphenyls in US meat, poultry and siluriform fish from 2018 to 2019

Daily dietary exposure estimates from beef, pork, chicken, turkey and siluriform fish were calculated using toxic equivalency (TEQ) data from the U.S. Department of Agriculture’s survey of dioxins and dioxin-like compounds (DLCs) in the domestic meat supply and consumption data. Exposure estimates for the whole population and age groups were based on mean consumption of a commodity and mean or 90th percentile TEQ dioxin levels from the survey. Ratios of the exposure estimates to the U.S. EPA oral reference dose (RfD) of 0.7 pg TEQ/kg bw/day were calculated to determine if domestic meat might contribute materially to consumer exposure. In general, normal consumption of lean beef, pork, chicken and turkey will not cause exposures exceeding the RfD. Non-lean meats will have higher dioxin levels as dioxins accumulate in fat, therefore consumption of non-lean meat might cause higher exposure than compared to lean meat. However, on a mean basis, none of the exposure estimates for non-lean beef, pork, chicken or turkey exceeded the RfD for any of the age groups. For some age groups, especially toddlers, there are commodities such as non-lean beef in the 90th percentile of dioxin TEQs and siluriform fish that might exceed the RfD on occasion.

Occurrence, distribution, sourceapportionment, ecological and health risk assessment of heavy metals in water, sediment, fish and prawn from Ojo River inLagos, Nigeria.

The study investigates the occurrence and bioaccumulationof heavy metals in water, sediment,fish, and prawn from the Ojo River with a view to identify the source of origin and the associated ecological and human health risks. The result shows that heavy metal concentrations in water [As = 0.010, Cd = 0.001, Cr = 0.041, Cu = 0.019, Co = 0.050, Fe = 0.099, Pb = 0.006, Ni = 0.003, and Zn = 0.452(mg/L)]were within theacceptable limits. The heavy metals in the sediment [As = 0.050, Cd = 0.287, Cr = 0.509, Cu = 0.207, Co = 0.086, Fe = 33.093, Pb = 0.548, Ni = 0.153 and Zn = 4.249 (mg/kg)]were within their respective background levels orearth's crust and theTEL and PEL standardlimits. The bioaccumulation ofheavy metals in fish and prawntissues are in this hierarchical form: Fe > Zn > Cu > Cr > Ni > Co > Pb > Ar > Cd and Fe > Zn > Cu > Cr > Pb > Ar > Ni > Co > Cd, respectively. The bioaccumulation factors of heavy metals in fishranged from 0.893 - 16.611 and 1.056 - 49.204 in prawn, which were higher than the biota-sedimentation factors (BSAF) values, inferring that the fish and prawns of this study ingested heavy metals highly from watercolumn. The aggregated BSAF scores (fish = 5.584 and prawn = 9.137) showed that these organisms are good concentrators of heavy metals in sediments. The water quality index and other pollution indices (Singlepollutionindex, Heavymetal assessment index, and Heavy metalpollutionindex) demonstrates slightlycleanwater, with a moderate level of contamination. The HI values of heavy metals in water, fish, and prawn were lower than 1, implying non-carcinogenic risk in children or adults. The ADD and EDI values of the metals were within their respective oral reference doses (RfD). The TCR values showed that exposure to water, either by ingestion or dermal absorption and the consumption of P. obscura and M. vollenhovenii from the Ojo River would not induce cancer risks in people, though As, Cr, Cd, and Pb showed carcinogenic potentials. The sediment contamination indices such as CF, mCd, EF, and Igeo showed a moderate level of pollution. The ecological risk values (NMPI, mCd = 0.068, PLI = 0.016, and R.I = 86.651) of heavy metals implies "no-moderate risk" except for Cd, which showed high risk. The ecotoxicologicalparameters, m-PEL-Q (0.024) and m-ERM-Q (0.016) denotes low contamination and no probability of acute toxicity. The CV analysis showed high dispersions and variabilities in the distributions of the heavy metals in water. Other source analyses (Pearson's correlation matrix, PCA, and HCA) showed that both natural processes and anthropogenic activities are responsible for the occurrence of heavy metals in water and sediment from the Ojo River.

Assessment of heavy metal concentrations and bioaccumulation in the invasive round goby (Neogobius melanostomus) and associated risks to human health

The round goby (Neogobius melanostomus) is an invasive species that can be used as a raw material in the food industry and also as a bioindicator of heavy metal pollution in the environment. In this study, Cd, Co, Cr, Mo, Ni, and Pb were determined in water, bottom sediment, muscle, liver, gills, and gonads of round goby from Dąbie Lake, Szczecin Lagoon, and Puck Bay (all in southern Baltic Sea) using atomic absorption spectrometry. Fulton’s condition factor, gonadal and hepatosomatic indices (GSI, HSI) were calculated. Based on estimated daily intake (EDI), target hazard quotient (THQ), and carcinogenic risk (CR), we assessed the human health risk related to the consumption of heavy metals in the round goby. The fish had length and weight ranges of 15.0–16.7 cm and 55.3–80.9 g, respectively. Fulton’s condition factor ranged from 1.26 to 2.48 and was highest (p < 0.05) for fish from Dąbie Lake. The range of metal concentrations (in μg kg−1) ranged from 2.92 (Cd in muscles of fish from Szczecin Lagoon) to 106.4 (Ni in muscles of fish from Dąbie Lake). The highest concentrations of Cd, Co, Mo, and Pb were found in livers, Ni in muscles and gonads, and Cr in gills. The calculated EDIs were below the reference oral dose (RfD) and maximum for Cd (1.6% RfD) and Pb (15.1% RfD). The hazard quotient was less than 1. In conclusion, the round goby has a higher potential to accumulate metals from water than from bottom sediments. Consumption of its muscle should not pose a health risk (cancer risk can be considered acceptable). Due to Pb accumulation, moderate consumption should be recommended for pregnant women and children. Finally, our results indicate that the round goby (especially its liver) can be used as a bioindicator to monitor metal contamination of aquatic ecosystems.

Human health risks associated to trace elements and metals in commercial fish from the Brazilian Amazon

Fish constitutes the main protein source for the Amazonian population. However, the impact of different anthropogenic activities on trace element and metal accumulation in fish and their risks for human health at a regional scale remain largely unexplored. Here we assessed exposure levels of 10 trace elements and metals (Cr, Mn, Fe, Ni, Cu, Zn, As, Cd, Pb, and Hg) in 56 samples belonging to 11 different species of fish from the Brazilian Amazon. We studied the relationship between exposure levels, fish origin, and fish feeding habits, and assessed toxicological and carcinogenic risks for the Amazonian population. No significant correlation was found between sampling site and exposure levels to the studied elements, but a significant difference was found between the accumulation of some metals and the position of the fish species in the food chain. The concentrations of Cr and Hg in fish flesh were found to exceed the Brazilian limits for human consumption. This study shows that current fish consumption patterns can lead to estimated daily intakes of Hg, As and Cr that exceed the oral reference dose, thus posing a toxicological concern. Furthermore, carcinogenic risks may be expected due to the continued exposure to Cr and As. The results of this study show that the consumption of wild caught fish in the Amazon region should be controlled. Moreover, continued monitoring of trace element and metal contamination in fish and on the health of the Amazonian population is recommended, particularly for riverine and indigenous communities.

Introducing bio-indicator fish of the Persian Gulf based on health risk assessment of 27 commercial species

BackgroundThe increasing consumption of seafood may bring health risks. It will be especially important for the people living along the coasts who are highly dependent on seafood for food and income. MethodsIn this research, a comprehensive health risk assessment was performed on 27 species of high-consumption commercial fish sampled from stations located in Hormozgan province within the Northeast Persian Gulf. Concentrations of trace metals and their health risk were investigated. ResultsSpatial distribution of trace metals in commercial fish showed central stations including Kong and Greater Tonb have higher concentrations of all trace metals except Pb. Some metals showed a significant correlation between concentrations. Our finding indicated the average concentration of all trace metals except Ni in all species was below the concentrations proposed by WHO/FAO/USEPA. EDI for all metals in all species in both adult and child age groups was lower than its RfD (oral reference dose of trace metal) showing the daily consumption of these fish does not pose any health risk and implicates seafood consumption guidelines or policies. Values of THQ for each metal and HI for all metals were lower than 1 in all commercial fish indicating the lack of non-cancerous health risk through the long-term consumption of these fish. The research found potential health risks associated with the consumption of these fish, specifically related to the metals Cr, Ni, and Cd. ConclusionIn total, health risk indices proposed eight fish as bio-indicator species of the Persian Gulf. The findings emphasize the risk management of commercial fish consumption, especially bio-indicator species, in Hormozgan province, the Northeast Persian Gulf.

Acute Effects of Brevetoxin-3 Administered via Oral Gavage to Mice.

Brevetoxins (BTXs) constitute a family of lipid-soluble toxic cyclic polyethers mainly produced by Karenia brevis, which is the main vector for a foodborne syndrome known as neurotoxic shellfish poisoning (NSP) in humans. To prevent health risks associated with the consumption of contaminated shellfish in France, the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) recommended assessing the effects of BTXs via an acute oral toxicity study in rodents. Here, we investigated the effect of a single oral administration in both male and female mice with several doses of BTX-3 (100 to 1,500 µg kg-1 bw) during a 48 h observation period in order to provide toxicity data to be used as a starting point for establishing an acute oral reference dose (ARfD). We monitored biological parameters and observed symptomatology, revealing different effects of this toxin depending on the sex. Females were more sensitive than males to the impact of BTX-3 at the lowest doses on weight loss. For both males and females, BTX-3 induced a rapid, transient and dose-dependent decrease in body temperature, and a transient dose-dependent reduced muscle activity. Males were more sensitive to BTX-3 than females with more frequent observations of failures in the grip test, convulsive jaw movements, and tremors. BTX-3's impacts on symptomatology were rapid, appearing during the 2 h after administration, and were transient, disappearing 24 h after administration. The highest dose of BTX-3 administered in this study, 1,500 µg kg-1 bw, was more toxic to males, leading to the euthanasia of three out of five males only 4 h after administration. BTX-3 had no effect on water intake, and affected neither the plasma chemistry parameters nor the organs' weight. We identified potential points of departure that could be used to establish an ARfD (decrease in body weight, body temperature, and muscle activity).