Occurrence and Health Risk Assessment of Cadmium Accumulation in Three Tricholoma Mushroom Species Collected from Wild Habitats of Central and Coastal Croatia

The Mechanisms of Cadmium Toxicity in Living Organisms

Cadmium (Cd) is a toxic metal primarily found as a by-product of zinc production. Cd was a proven carcinogen, and exposure to this metal has been linked to various adverse health effects, which were first reported in the mid-19th century and thoroughly investigated by the 20th century. The toxicokinetics and dynamics of Cd reveal its propensity for long biological retention and predominant storage in soft tissues. Until the 1950s, Cd pollution was caused by industrial activities, whereas nowadays, the main source is phosphate fertilizers, which strongly contaminate soil and water and affect human health and ecosystems. Cd enters the human body mainly through ingestion and inhalation, with food and tobacco smoke being the primary sources. It accumulates in various organs, particularly the kidney and liver, and is known to cause severe health problems, including renal dysfunction, bone diseases, cardiovascular problems, and many others. On a cellular level, Cd disrupts numerous biological processes, inducing oxidative stress generation and DNA damage. This comprehensive review explores Cd pollution, accumulation, distribution, and biological impacts on bacteria, fungi, edible mushrooms, plants, animals, and humans on a molecular level. Molecular aspects of carcinogenesis, apoptosis, autophagy, specific gene expression, stress protein synthesis, and ROS formation caused by Cd were discussed as well. This paper also summarizes how Cd is removed from contaminated environments and the human body.

Spatio-temporal distribution of cadmium levels in Chinese population and its potential risk factors

Cadmium (Cd), a ubiquitous heavy metal, exists in numerous environmental matrices and has severe adverse effects on various human organs and tissues. This research evaluates blood and urine Cd levels in the Chinese population through data mining using Monte Carlo simulation (MCS). A total of 168 scientific studies (120 on urine and 48 on blood) published between January 1980 and December 2020, reflecting a population of 109,743 individuals in China, were included in the study. The results indicate that the blood and urine Cd levels in the Chinese population exhibited a peak from 1990 to 1995 and remained stable after 1995, averaging 1.21 μg/L of blood Cd (BCd) and 0.61 μg/L of urine Cd (UCd). The spatial trend of Cd levels varied significantly. Shandong, Zhejiang, Heilongjiang, and Guangdong provinces were identified as the top provinces with high Cd levels, which were related to factors such as tobacco sales, E-waste amounts, and contaminated rice. Additionally, the study highlights that BCd concentrations are highest among preschool-aged individuals, whereas school-age and adolescent groups exhibit the lowest levels. However, no significant difference existed among the different age groups. Males showed significantly higher Cd levels than females in the general population. Moreover, exposure to smoking, drinking, and staple food preferences had an impact on Cd levels. Furthermore, this comprehensive study, using biological monitoring and data mining, provides valuable information on Cd pollution levels in the Chinese population. It presents a statistical analysis that can aid decision-makers in implementing effective measures to control potential Cd pollution and improve the health of vulnerable populations.

Mechanism of cadmium-induced nephrotoxicity

Heavy metals are found naturally in our environment and have many uses and applications in daily life. However, high concentrations of metals may be a result of pollution due to industrialization. In particular, cadmium (Cd), a white metal abundantly distributed in the terrestrial crust, is found in mines together with zinc, which accumulates after volcanic eruption or is found naturally in the sea and earth. High levels of Cd have been associated with disease. In the human body, Cd accumulates in two ways: via inhalation or consumption, mainly of plants or fish contaminated with high concentrations. Several international organizations have been working to establish the limit values of heavy metals in food, water, and the environment to avoid their toxic effects. Increased Cd levels may induce kidney, liver, or neurological diseases. Cd mainly accumulates in the kidney, causing renal disease in people exposed to moderate to high levels, which leads to the development of end-stage chronic kidney disease or death. The aim of this review is to provide an overview of Cd-induced nephrotoxicity, the mechanisms of Cd damage, and the current treatments used to reduce the toxic effects of Cd exposure.

Preface to the Special Issue 'Heavy Metals in Mushrooms'

Population growth, intensive industrialization and urbanization have led to environmental pollution, especially soil and water pollution [...].

Nutritional Composition and Odor-Contributing Volatile Compounds of the Edible Mushroom Cantharellus alborufescens

Chanterelles are one of the most highly valued wild edible mushroom genera worldwide. This work aimed to investigate the nutritional characteristics and volatile compounds' profile of Cantharellus alborufescens for the first time. Proximate analysis was performed according to the Association of Official Agricultural Chemists, while the mineral contents and the volatile compounds were determined using ICP-MS and GC-MS, respectively. C. alborufescens had an average of 25.8% protein, 5.5% fat, 12.7% ash, and 55.9% carbohydrates, including 11.4% fiber per dw of mushroom. Further analyses of the fat and protein contents revealed high amounts of polyunsaturated fatty acids as well as monosodium glutamate-like amino acids. Linoleic acid (42.0% of fat) and oleic acid (28.6% of fat) were the major fatty acids, while leucine (1.2%) and lysine (0.9%) were the most abundant essential amino acids. The results showed that C. alborufescens contained 3.1 µg/g vitamin D2 and 4.9 mg/g vitamin E per dw, as well as notable quantities of macro- and microelements, such as potassium, calcium, magnesium, and iron. GC-MS analysis revealed various volatile compounds such as acetaldehyde, n-hexanal, 3-methylbutanal, 1-octen-3-ol, etc. In conclusion, this study supports the use of C. alborufescens as a food rich in fiber and vitamin E, with a suitable amount of protein and other nutrients.

Platinum and Palladium Accumulation in Edible Mushroom Boletus aereus Bull. Growing in Unpolluted Soils of Sicily Region (Italy)

Human exposure to certain metals occurs indirectly through diet. This study was conducted to determine the content of Pt and Pd in fruiting bodies of Boletus aereus Bull. collected from several wooded areas of Sicily with different substrates (sedimentary and volcanic) with limited anthropogenic influence. Determinations were performed by coupled plasma-mass spectrometry (ICP-MS) to quantify Pt and Pd. The concentrations of investigated Pt and Pd in mushroom samples ranged from 0.31 to 3.09 ng g-1 for palladium and 0.21 to 4.22 ng g-1 for platinum. The results of the present study suggest that commonly consumed Boletus aereus mushrooms do not accumulate significant levels of Pt and Pd as demonstrated by bioconcentration factor (BCF) values, and their content is lower than in other food products. Additionally, based on the calculated daily intake rates of Pt and Pd, it can be concluded that occasional consumption of fruiting bodies of B. aereus collected in Sicily is safe. The proposed methodological approach appears to be fully adequate for the reliable quantification of Pt and Pd. The data obtained in this investigation confirm that mushrooms are probative of a significant portion of the total exposure to PGEs due to the diet.

Risk Assessment of Heavy Metals Occurrence in Two Wild Edible Oyster Mushrooms (Pleurotus spp.) Collected from Rajaji National Park

This study aimed at assessing the concentration of six heavy metals (Cd, Cr, Cu, Fe, Mn, and Zn) in two wild edible oyster mushrooms (Pleurotus ostreatus and Pleurotus djamor) collected from Rajaji National Park in Haridwar, India. For this purpose, mushroom samples were collected from selected locations (forest, residential, tourist, industrial areas, and transportation activities) from June 2021 to July 2022 and subsequently analyzed for selected heavy metals using atomic absorption spectroscopy (AAS). Results showed that both Pleurotus spp. had significantly varying (p < 0.05) concentrations of heavy metals. However, P. ostreatus showed relatively higher concentration levels of these metals compared to P. djamor. The mean concentrations (mg/kg dry weight) of the Cd, Cr, Cu, Fe, Mn, and Zn in P. ostreatus and P. djamor were 0.10 and 0.08, 0.87 and 0.64, 16.19 and 14.77, 28.49 and 27.15, 9.93 and 8.73, and 18.15 and 15.76, respectively. As indicated by the multivariate analysis tools i.e., principal component analysis (PCA) and hierarchical cluster analysis (HCA), the locations near the residential, industrial, and transportation activities had higher concentration levels of heavy metals. Moreover, the health risk studies using the target hazard quotient (THQ < 1) showed no significant health risk as the consumption of both Pleurotus spp., except for at one location, had high-traffic activities. The findings of this study provide vital information about the occurrence of potentially toxic heavy metals in wild edible Pleurotus spp. in Rajaji National Park in Haridwar, India representing a safeguard for mushroom consumers.