Risk estimation to human health caused by the mercury content of Sushi and Sashimi sold in Japanese restaurants in Brazil

Although fish is a healthy alternative for meat, it can be a vehicle for mercury (Hg), including in its most toxic organic form, methylmercury (MeHg). The objective of the present study was to estimate the risk to human health caused by the consumption of sushi and sashimi as commercialized by Japanese food restaurants in the city of Campinas (SP, Brazil). The total Hg content was determined by atomic absorption spectrometry with thermal decomposition and amalgamation, and the MeHg content calculated considering that 90% of the total Hg is in the organic form. The health risk was estimated from the values for the provisional tolerable weekly ingestion (PTWI) by both adults and children. The mean concentrations for total Hg were: 147.99, 6.13, and 3.42 µg kg^?1 in the tuna, kani, and salmon sushi samples, respectively, and 589.09, 85.09, and 11.38 µg kg^?1 in the tuna, octopus and salmon sashimi samples, respectively. The tuna samples showed the highest Hg concentrations. One portion of tuna sashimi exceeded the PTWI value for MeHg established for children and adults. The estimate of risk for human health indicated that the level of toxicity depended on the type of fish and size of the portion consumed.     

Pesticide residue removal in classic domestic processing of tomato and its effects on product quality

This study was undertaken to evaluate the effectiveness of several household practices (washing with water or acidic, alkaline, and oxidizing solutions, and peeling) in minimizing pesticide residue contamination of tomatoes, as well as the impact on the quality of the treated fruit. Tests were performed using two systemic fungicides (azoxystrobin and difenoconazole) and one contact fungicide (chlorothalonil). Solid-liquid extraction with low temperature partition (SLE/LTP) and liquid-liquid extraction with low temperature partition (LLE/LTP) were used to prepare the samples for pesticides determination by gas chromatography. Washing the tomatoes with water removed approximately 44% of chlorothalonil, 26% of difenoconazole, and 17% of azoxystrobin. Sodium bicarbonate (5%) and acetic acid (5%) solutions were more efficient, removing between 32 and 83% of the residues, while peeling removed from 68 to 88% of the pesticides. The washing solutions altered some fruit quality parameters, including acidity and chroma, and also caused weight loss. Acetic acid (0.15 and 5%) and hypochlorite (1%) solutions had the greatest effect on these parameters.     

Dental enamel as biomarker for environmental contaminants in relevant industrialized estuary areas in São Paulo,Brazil

Heavy metal contamination is a long-standing and very well-known public health problem, and its exposure can cause damage to several organs of human body, especially on the central nervous system of young children and teenagers. The aim of this article is to evaluate lead, cadmium, and manganese contamination in 125 children from 6 to 13 years old living in contaminated areas during the period from 2006 to 2009 (São Vicente, Cubatão Downtown, Bertioga and Cubatão Pilões/Água Fria). This estuary area is the most important example of environmental degradation by chemicals from industrial sources. This is a cross-sectional study through clinical examinations and dental enamel tests. All mothers from these children lived in the area since before the pregnancy. Lead, cadmium, and manganese levels (μg/g) were measured on dental enamel samples through graphite furnace atomic absorption spectrometry, searching for the occurrence of heavy metals. The mean lead concentrations were 139.48 μg/g in Cubatão Pilões/Água Fria, 170.45 μg/g in Cubatão Downtown, 213.52 μg/g in São Vicente, and 151.89 μg/g in Bertioga. The mean cadmium concentrations were 10.83 μg/g in Cubatão Pilões/Água Fria, 12.58 μg/g in Cubatão Downtown, 10.92 μg/g in São Vicente, and 14.57 μg/g in Bertioga. The mean manganese concentrations were 23.49 μg/g in Cubatão Pilões/Água Fria, 30.90 μg/g in Cubatão Downtown, 41.46 μg/g in São Vicente, and 42.00 μg/g in Bertioga. Dental surface enamel may be used as an efficient biomarker of past environmental exposure to lead, manganese, and cadmium which are associated to well-known sources of heavy metal contamination. The results suggest that the evaluated children were exposed to sources of lead, cadmium, and manganese since before their conceptions. Although Bertioga initially was chosen as a control area of this study, it was also was verified to have heavy metal contamination on examined children.     

Treatment of bleach pulp mill effluent by MF-MBR

The types of treatment most commonly used by pulp mills are biological treatments in combination with sedimentation or coagulation/flocculation as pretreatment. The main issues faced by these types of treatment are low efficiency in the removal of organic matter and the loss of aggregate value for the recovered fiber. Therefore, this study aims to evaluate the use of microfiltration (MF) combined with a membrane bioreactor (MBR) for the treatment of bleach pulp mill effluents. The results showed that the use of the MF-MBR system was an excellent alternative for the treatment of bleach pulp mill effluents with an average COD removal of 95%. The microfiltration allowed the recovery of fibers, which can be returned to the production process without losing economic value, and produced a better quality effluent for further treatment in the MBR. The MBR presented high efficiency removal of organic matter.     

Acute toxicity and ecotoxicological risk assessment of rice pesticides to Lithobates catesbeianus tadpoles

The objective of this study was to determine the acute toxicity of some pesticides used in irrigated rice farming to Lithobates catesbeianus tadpoles. The LC_50-96h for commercial formulations containing bentazon, penoxsulam, vegetable oil, permethrin and carbofuran, separately and their mixtures, were determined at the proportions commonly used in the field. The limits of risk concentrations of these products for the studied species were also established. The LC_50-96h for tadpoles was 4,530 mg L^?1 for bentazon; 7.52 mg L^?1 for penoxsulam + 145.66 mg L^?1 of vegetable oil; 81.57 mg L^?1 for vegetable oil; 0.10 mg L^?1 for permethrin; 29.90 mg L^?1 for carbofuran (active ingredients), and 38.79 times the dose used in the field for the mixture of these products. The environmental risk was determined only for permethrin, and care should be taken when using the vegetable oil.     

Changes in hematological and serum biochemical values in jundiá Rhamdia quelen due to sub-lethal toxicity of cypermethrin

Jundiá (Rhamdia quelen, Quoy and Gaimard), a South American teleostean fish, was exposed to sub-lethal concentrations of cypermethrin (30% and 45% of the 48-h LC(50) value of 0.265 ppm) for 2, 4 or 8 days. Serum biochemical and hematological values and behavioral changes were studied. The 30% LC(50), 0.08 ppm, produced significant increases in Mg(2+), P, K(+), creatinine, urea, glucose, cholesterol, aspartate aminotransferase and alkaline phosphatase levels, and reduction in total proteins and triglycerides in serum. The 45% LC(50), 0.12 ppm, produced significant increase in Na(+), Mg(2+), P, K(+), creatinine, urea, glucose, cholesterol, and alkaline phosphatase, and reduction in triglycerides and alanine aminotransferase levels in serum. At this concentration, the fish showed behavior changes such as hyper-excitability, asphyxia, and widening of mouth and operculum. The hematological values remained normal, except for hemoglobin concentrations and the mean corpuscular hemoglobin concentration, which increased with exposure to 0.08 ppm and 0.12 ppm cypermethrin. Results of the present work show that biochemical analysis of serum can be useful to detect incipient cypermethrin intoxication of the shoal.     

The role of private rural properties for conserving native vegetation in Brazilian Southern Amazonia

Regional Environmental Change - The State of Mato Grosso in Brazil has undergone intensive land use changes over the past decades. Native ecosystems have been converted into agrosystems for the...     

Vertical structure of very nearshore larval fish assemblages in a temperate rocky coast

Small-scale vertical patterns of larval distribution were studied at a very nearshore larval fish assemblage, during the spring–summer period of several years, at two depth strata (surface and bottom) using sub-surface and bottom trawls. A total of 4,589 larvae (2,016 from surface samples and 2,573 from bottom samples) belonging to 62 taxa included in 22 families were collected. Most larvae belonged to coastal species. Although inter-annual variations in larval density and diversity could be found, total larval abundance was always higher near the bottom whereas diversity was higher at the surface. A marked distinction between the structure of surface and bottom assemblages was found. Sixteen taxa explained 95% of the similarity among surface samples. Larvae which contributed most to this similarity included species like clupeiformes, sparids and serranids, and also blenniids, tripterygiids and some labrids. In the bottom samples, fewer species were present, with only six taxa, almost exclusively from species which lay demersal eggs, contributing to 95% of the similarity between samples. Larvae present at the surface were significantly smaller than at the bottom. For some of the most abundant species found at the bottom, only small larvae occurred at the surface while the whole range of sizes was present at the bottom, indicating that larvae may be completing the entire pelagic phase near the adults’ habitat. These results indicate that larval retention near the reefs probably occurs for these species, although for others dispersal seems to be the prevailing mechanism.     

Use of organic coagulant/flocculant for treatment of effluents generated in intensive rearing of swine

Separation of water for reuse is essential in an effluent treatment system, especially in activities with high water consumption, such as a pig production system. The objective of this work was to evaluate the efficiency of Tanfloc SG^® coagulant tannin/organic flocculant used to treat effluent generated during the intensive rearing of swine. For the evaluation, laboratory and in situ tests (field test) were performed. The laboratory tests were performed to define the concentration (1 and 16%), dosage (0, 0.1, 0.2, 0.3, 0.4, 0.5, 1.0, 2.0, 4.0, 8.0, and 16.0 milliliters of the solution), and time (24, 48, 72, and 96 hours) of coagulation/flocculation treatment of the solid portion of the effluent. The parameters pH, turbidity, oxidation reduction potential, dissolved oxygen, and electroconductivity (in microsiemens per centimeter) were evaluated using a multiparameter probe and the parameters ammonia (NH₃), nitrate (NO₃), and nitrite (NO₂) in the laboratory, in relation to the coagulation/flocculation time of the solid part of the effluent. The use of tannin as a coagulant/flocculant of plant origin in the treatment of swine effluents was effective in reducing turbidity and concentrations of ammonia, nitrite, and nitrate, and it allowed separation of the solid–liquid phase in approximately 68% as liquid phase.     

Hepatitis A Virus,Hepatitis E Virus,and Rotavirus in Foods of Animal Origin Traded at the Borders of Brazil,Argentina, and Uruguay

The aim of this study was to investigate hepatitis A virus (HAV), hepatitis E (HEV), and rotavirus (RV) in fresh and processed meat traded on the border of Brazil with Argentina and Uruguay. In total, 159 samples of raw and processed foods of animal origin were collected in Paso de los Libres, Argentina (n?=?53 raw meat, n?=?24 processed meat) and Rivera, Uruguay (n?=?55 raw meat, n?=?18 processed meat), or were seized by the Brazilian International Agricultural Surveillance System—VIGIAGRO (Brazil–Argentina border) (n?=?8 raw meat, n?=?1 bush meat). All samples were tested for the presence of HAV, HEV, and RV genomes. HAV genes were detected in 18.23% of samples and RV genes in 23.89%. No HEV-positive samples were detected. HAV was also detected in two of the VIGIAGRO samples. Processed meats from Argentina and Uruguay had a higher rate of HAV and RV than raw meat (P?>?0.05). The median HAV in the Argentinian and Uruguayan samples was 6.9?×?10⁴ and 3.5?×?10³ copies/g, respectively. The presence of RV viral genes in raw meats from Argentina was significant, and this was not observed in processed meats. The presence of HAV and RV genes in a significant portion of products from Argentina and Uruguay is a potential source of human infection. This also indicates precarious conditions of acquisition, processing, and manipulation, which could be improved by improved regulation of food across borders.