Possible influence of natural events on heavy metals exposure from shellfish consumption: a case study in the north-East of Italy

Essential and Non-Essential Elements in Razor Clams (Solen marginatus, Pulteney, 1799) from the Domitio Littoral in Campania (Southwestern Tyrrhenian Sea, Italy)

The levels of essential (Cu, Cr, Co, Mn, Se, Zn) and non-essential (As, Be, Bi, Cd, Cs, Ga, Ni, Pb, Sr, Tl, U, V) trace elements were studied in razor clams (Solen marginatus) collected from the Tyrrhenian coast of Southern Italy at five selected sites along the Domitio littoral in the Campania region. The main objectives of this study were to assess the contamination status of these bivalve mollusks and to evaluate the risks to the environment and consumers due to metal contamination. The concentrations of 18 trace elements were determined after microwave-assisted mineralization and by inductively coupled plasma mass spectrometry (ICP-MS). Concentrations of the toxic elements Pb and Cd were below the maximum levels established by Commission Regulation (EC) 1881/2006, while higher average concentrations of arsenic were found at each of the five sites studied. Regarding the other trace elements, contamination levels followed the order: Zn > Sr > Mn > Cu > Se > Cr > V > Ni > Co > Ga > Cs > Be > U > Bi > Tl. No significant differences among the sites were found with regard to any of the trace elements analyzed, and element levels in razor clams did not reflect sediment contamination. The results demonstrated the substantial food safety of the razor clams in this area with respect to heavy metals but revealed a potential health risk due to arsenic contamination in all the areas sampled.

Real-Time Environmental Monitoring for Aquaculture Using a LoRaWAN-Based IoT Sensor Network

IoT-enabled devices are making it easier and cheaper than ever to capture in situ environmental data and deliver these data-in the form of graphical visualisations-to farmers in a matter of seconds. In this work we describe an aquaculture focused environmental monitoring network consisting of LoRaWAN-enabled atmospheric and marine sensors attached to buoys on Clyde River, located on the South Coast of New South Wales, Australia. This sensor network provides oyster farmers operating on the river with the capacity to make informed, accurate and rapid decisions that enhance their ability to respond to adverse environmental events-typically flooding and heat waves. The system represents an end-to-end approach that involves deploying a sensor network, analysing the data, creating visualisations in collaboration with farmers and delivering them to them in real-time via a website known as FarmDecisionTECH®. We compared this network with previously available infrastructure, the results of which demonstrate that an in situ weather station was ∼5 ∘C hotter than the closest available real-time weather station (∼20 km away from Clyde River) during a summertime heat wave. Heat waves can result in oysters dying due to exposure if temperatures rise above 30 ∘C for extended periods of time (such as heat waves), which will mean a loss in income for the farmers; thus, this work stresses the need for accurate in situ monitoring to prevent the loss of oysters through informed farm management practices. Finally, an approach is proposed to present high-dimensional datasets captured from the sensor network to oyster farmers in a clear and informative manner.

Risk Assessment of Cd, Cu, and Pb from the consumption of hunted meat: red-legged partridge and wild rabbit

The objective was to assess that potential health risk from Cd, Cu, and Pb, through the consumption of hunted red-legged partridge and wild rabbit meat, with special focus on the population of hunters and their relatives. Mineral content was analyzed by atomic absorption methods (F-AAS for Cu and GF-AAS for Cd and Pb) after microwave digestion of lyophilized samples. The average concentrations of these elements were 0.008 and 0.01 mg/kg for Cd; 1.41 and 1.63 mg/kg for Cu and 0.98 and 1.28 mg/kg for Pb in wild rabbit and red-legged partridge meat respectively. The dietary, risk assessment was performed by assuming two intake scenarios based on the obtained results of the survey on game meat consumption and the current maximum recommended intakes of Cd, Cu, and Pb, and then, the hazard quotients (THQ and TTHQ) were calculated. The data show that exposure to these metals from eating red-legged partridge and wild rabbit meat from a hunting provenance is relatively low and generally greater in the hunter population. The risk assessment revealed that moderate or low consumption of meat of these species does not offer a significant public health risk. Moreover, hazard quotients values for these metals of red-legged partridge and rabbit meat consumption in hunters and nonhunters are below 1. However, a high Pb content in the meat of these species and a high consumption may pose a greater health risk to hunters.

Heavy metal spatial and temporal trends (2008-2018) in clams and mussel from Adriatic Sea (Italy): Possible definition of forecasting models

In 2008-2018, 1458 georeferenced samples of clams and 343 of mussels were harvested in Italy from classified areas along Marche coast and analyzed within food-safety monitoring plans. Pb, Cd, V, Ni, Cr, and As median levels (mg kg^-1) were 0.09, 0.08, 0.29, 0.77, 0.35, and 2.35 in clams and 0.16, 0.15, 0.46, 0.48, 0.25, and 3.34 in mussels. The reported levels were comparable with the published ones, and Hg always fell below LOQ (0.025 mg kg^-1). Pb and Cd datasets, based on quarterly results, show a decreasing trend in clams and constant baseline value for mussels. Time-trends and forecasting models represent an asset to predict emerging food safety/security risks. The metal levels in mussels and clams from the same area allow environmental safety assessment and thus enable the evaluation of contaminants in both water column and sediment. Monitoring of elements that are not regulated may help in preserving food and environmental safety.

Cadmium and Lead Exposure, Nephrotoxicity, and Mortality

The present review aims to provide an update on health risks associated with the low-to-moderate levels of environmental cadmium (Cd) and lead (Pb) to which most populations are exposed. Epidemiological studies examining the adverse effects of coexposure to Cd and Pb have shown that Pb may enhance the nephrotoxicity of Cd and vice versa. Herein, the existing tolerable intake levels of Cd and Pb are discussed together with the conventional urinary Cd threshold limit of 5.24 μg/g creatinine. Dietary sources of Cd and Pb and the intake levels reported for average consumers in the U.S., Spain, Korea, Germany and China are summarized. The utility of urine, whole blood, plasma/serum, and erythrocytes to quantify exposure levels of Cd and Pb are discussed. Epidemiological studies that linked one of these measurements to risks of chronic kidney disease (CKD) and mortality from common ailments are reviewed. A Cd intake level of 23.2 μg/day, which is less than half the safe intake stated by the guidelines, may increase the risk of CKD by 73%, and urinary Cd levels one-tenth of the threshold limit, defined by excessive ß₂-microglobulin excretion, were associated with increased risk of CKD, mortality from heart disease, cancer of any site and Alzheimer's disease. These findings indicate that the current tolerable intake of Cd and the conventional urinary Cd threshold limit do not provide adequate health protection. Any excessive Cd excretion is probably indicative of tubular injury. In light of the evolving realization of the interaction between Cd and Pb, actions to minimize environmental exposure to these toxic metals are imperative.

Hummingbird-Leaves-Reared Black Soldier Fly Prepupae: Assessment of Nutritional and Heavy Metal Compositions

Black soldier fly (BSF) larva is an attractive animal feed replacer due to its noticeable nutritional content. However, the conventional rearing method often resulted in BSF with undesirably high heavy metal residues that are harmful to animals. In this work, putrefied Sesbania grandiflora (S. Grandiflora) leaves were employed as feed to rear BSF larvae. The resultant BSF prepupae were found to contain 43.5% protein and 16.7% fat, reflecting a comparable protein content and a 2-fold reduction in crude fat than those reared using conventional kitchen waste. Moreover, high quantities of arginine (25.4 g/kg dry matter basis (DM)), carnitine (32.9 g/kg DM), and short-chain fatty acids, including lauric (40.00%), palmitic (19.20%), and oleic (12.10%) acids, have also been noticed in the BSF prepupae. Furthermore, the BSF larvae have been recorded with 0.185 mg/kg chromium, 0.380 mg/kg selenium, and mercury below the detection limit, which is far lower than those reared using conventional kitchen and agricultural wastes (≈1.7 mg/kg chromium, 1.2 mg/kg selenium, and 0.2 mg/kg mercury). Overall, the study shows that the nutritional quality of BSF prepupae is extensively improved when using S. Grandiflora as their feed. The resultant BSF prepupae may serve as an alternative feed for animal rearing.

Heavy metals in commercial fish and seafood products and risk assessment in adult population in Bosnia and Herzegovina

This work investigates the level of exposure to cadmium (Cd), mercury (Hg), and lead (Pb) via fish and seafood products in adult population in Bosnia and Herzegovina (BiH). Metals content was determined in seven commercial species of fish and seafood products widely available and consumed in BiH. Analysis of Cd and Pb was performed by GFAAS (Graphite furnace atomic absorption spectrometry), and analysis of Hg by FIAS AAS (flow injection cold vapour atomic absorption spectrometry) in accredited laboratory for food analysis. The health risk was determined by the estimated weekly intake, hazard index, target hazard quotients, and percent of tolerable weekly intake or percent of benchmark dose lower confidence limit. Concentration above the maximum residue level (MRL) set in the European Union was found in only one sample (Hg in mackerel). Cd content was generally high in squid, approaching the corresponding MRL in two samples. The hazard index was close to 1 in bluefin tuna and mackerel, mostly due to Hg content. These two fish species should be consumed in moderation, especially by pregnant women. While consumption of various fish and seafood on average is not of significant concern, health risk could not be ruled out for high consumers.