Toxicological and behavioral analyses indicates the safety of a biofertilizer in the non-target D. melanogaster.

The demand for food to feed the growing world population has been promoting the indiscriminate use of chemical fertilizers, which can be detrimental to the environment. In order to maintain high crop productivity without damaging the ecosystem, biofertilizers have emerged as alternative to reduce the use of chemical fertilizers. So, environmentally safer biofertilizer can replace the exploitation of more toxic chemical fertilizer. Here, the fly Drosophila melanogaster was used to study the potential toxicity of the biofertilizer Beifort®. Flies were exposed to high concentrations of Beifort® in the diet (1.8 mL/L, 9.0 mL/L and 18 mL/L), and morphological and behavioral endpoints of toxicity were analyzed (development from egg to adult age, flies longevity, climbing performance, memory and learning of an associative learning, larvae digestive tract damage and plasmid DNA break). Beifort® did not modify flies development, survival, digestive track cell damage, locomotor activity or memory. Beifort® did not induce DNA breakage in vitro and had no toxicity to the non-target D. melanogaster after in vivo exposure. Thus, in addition of promoting the sustainable use of agricultural wastes, the exploitation of Beifort® can contribute to decrease the use of chemical fertilizers.

Induced Hepatic Glutathione and Metabolomic Alterations Following Mixed Pesticide and Fertilizer Exposures in Juvenile Leopard Frogs (Lithobates sphenocephala).

The increasing use of agrochemicals, alone and in combination, has been implicated as a potential causative factor in the decline of amphibians worldwide. Fertilizers and pesticides are frequently combined into single-use tank mixtures for agricultural applications to decrease costs while meeting the food demands of a growing human population. Limited data are available on the effects of increased nitrogen levels in nontarget species, such as amphibians, and therefore investigating alterations in the nitrogen cycle and its impacts on amphibians needs to be considered in best management practices going forward. The objective of the present study was to elucidate the impact of fertilizer (urea) and herbicide (atrazine and/or alachlor) tank mixtures on the hepatic metabolome of juvenile leopard frogs as well as to investigate alterations in oxidative stress by relating these changes to glutathione (GSH) levels. Herbicide exposure only moderately increased this parameter in amphibians, however, urea alone and in combination with either atrazine or alachlor statistically elevated GSH levels. Interestingly, urea also inhibited pesticide uptake: calculated bioconcentration factors were greatly decreased for atrazine and alachlor when urea was present in the exposure mixture. Metabolomic profiling identified fluxes in hepatic metabolites that are involved in GSH and carbohydrate metabolic processes as well as altered intermediates in the urea cycle. Ultimately, understanding the biological impacts of nitrogenous fertilizers alone and in combination with pesticide exposure will inform best management practices to conserve declining amphibian populations worldwide. Environ Toxicol Chem 2022;41:122-133. © 2021 SETAC.

Morphological and transcriptomic alterations in neonatal lamb testes following developmental exposure to low-level environmental chemical mixture.

Exposure to anthropogenic environmental chemical mixtures could be contributing to the decline in male reproductive health. This study used the biosolid treated pasture (BTP) sheep model to assess the effects of exposure to low-dose chemical mixtures. Maternal BTP exposure was associated with lower plasma testosterone concentrations, a greater proportion of Sertoli cell-only seminiferous tubules, and fewer gonocytes in the testes of neonatal offspring. Transcriptome analysis highlighted changes in testicular mTOR signalling, including lower expression of two mTOR complex components. Transcriptomic hierarchical analysis relative to the phenotypic severity demonstrated distinct differential responses to maternal BTP exposure during pregnancy. Transcriptome analysis between phenotypically normal and abnormal BTP lambs demonstrated separate responses within the cAMP and PI3K signalling pathways towards CREB. Together, the results provide a potential mechanistic explanation for adverse effects. Exposure could lower gonocyte numbers through mTOR mediated autophagy, but CREB mediated survival factors may act to increase germ cell survival.

Green Synthesis of Zeolite/Fe2O3 Nanocomposites: Toxicity & Cell Proliferation Assays and Application as a Smart Iron Nanofertilizer.

PURPOSE: The aim of this study was to prepare zeolite/iron (III) oxide nanocomposites (zeolite/Fe2O3-NCs) as a smart fertilizer to improve crop yield and soil productivity. METHODS: Zeolite/Fe2O3-NCs were successfully produced by loading of Fe2O3-NPs onto the zeolite surface using a quick green precipitation method. The production of zeolite/Fe2O3 nanocomposites was performed under a mild condition using environmentally friendly raw materials as a new green chemistry method. The product was characterized using several techniques such as near and far Fourier-transform infrared spectroscopy (FT-IR), powder X-ray diffraction (PXRD), energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). RESULTS: The results confirmed the formation of Fe2O3-NPs with mean particle sizes of 1.45, 2.19, and 2.20 nm on the surface of the zeolite per amount of 4, 7 and 12 wt% Fe2O3-NPs, respectively. Such results indicated that the size of the Fe2O3-NPs did not significantly change when Fe amounts increased from 7 to 12 wt% for the zeolite/Fe2O3-NCs. In terms of medical applications, in vitro cell studies demonstrated that zeolites and zeolite/Fe2O3-NCs were generally non-toxic to human fibroblast cells and significantly pernicious to human malignant melanoma cells. From MTS cytotoxicity assays, the concentration of Fe2O3 within the zeolite/Fe2O3-NCs that was effective at inhibiting the growth of malignant melanoma cells by 50% (the IC50 value) was ~14.9 wt%. The three types of nanocomposites were further tested as an iron smart nanofertilizer for the slow-release of iron ions. CONCLUSION: Advantages of this project include the production of non-toxic nanocomposites as a smart fertilizer to develop crops while the reaction involves the use of commercial and natural materials as low-cost raw materials with low energy usage due to a mild reaction condition, as well as the use of an environmentally friendly solvent (water) with no toxic residues.

Investigation of pesticide exposure by genotoxicological, biochemical, genetic polymorphic and in silico analysis.

Soybean farmers are exposed to various types of pesticides that contain in their formulations a combination of chemicals with genotoxic and mutagenic potential. Therefore, the objective of this paper was to evaluate the genetic damages caused by this pesticide exposure to soybean producers in the state of Mato Grosso (Brazil), regarding biochemical, genetic polymorphic and in silico analyses. A total of 148 individuals were evaluated, 76 of which were occupationally exposed and 72 were not exposed at all. The buccal micronucleus cytome assay (BMCyt) detected in the exposed group an increase on DNA damage and cell death. No inhibition of butyrylcholinesterase (BchE) was observed within the exposed group. The detection of inorganic elements was made through the particle-induced X-ray emission technique (PIXE), which revealed higher concentrations of Bromine (Br), Rubidium (Rb) and Lead (Pb) in rural workers. A molecular model using in silico analysis suggests how metal ions can cause both DNA damage and apoptosis in the exposed cells. Analysis of the compared effect of X-ray Repair Cross-complement Protein 1 (XRCC1) and Paraoxonase 1 (PON1) genotypes in the groups demonstrated an increase of binucleated cells (exposed group) and nuclear bud (non-exposed group) in individuals with the XRCC1 Trip/- and PON1 Arg/- genes. There was no significant difference in the telomere (TL) mean value in the exposed group in contrast to the non-exposed group. Our results showed that soybean producers showed genotoxic effect and cell death, which may have been induced by exposure to complex mixtures of agrochemicals and fertilizers. In addition, XRCC1 Arg/Arg could, in some respects, provide protection to individuals.

Ammonia exposure induced abnormal expression of cytokines and heat shock proteins via glucose metabolism disorders in chicken neutrophils.

Ammonia (NH3) is a highly irritant, alkaline gas. Atmospheric emission of NH3 was recognized as an environmental challenge. As a global issue, the NH3 emission survey with spatially detailed information demonstrated that the sources of atmospheric NH3 include agriculture (livestock wastes, fertilizers) and some industrial activities. As an environmental pollution, excessive NH3 exposure can induce many bird dysfunction. Neutrophils respond to multiple invading pathogens through different mechanisms. In order to investigate the effect of NH3 exposure on broilers' neutrophil, 1-day-old broilers were treated with/without NH3 for 28 days. We extracted neutrophils from peripheral blood of chicken with/without NH3 exposure and subsequently stimulated with PMA. Changes of cytokines and inflammatory bodies, heat shock proteins (HSPs), and glucose metabolism of neutrophil were examined in both cases. We not only explored that the index associated with inflammation changed due to NH3 exposure but also observed the status of neutrophils which was treated with PMA stimulation. After NH3 exposure, IL-1ß and IL-6 were significantly increased on broilers neutrophil. Inflammatory-related factors (NLRP3, ASC, and caspase-1) were significantly elevated. The mRNA expression of HSP70 and HSP90 was increased significantly. All glucose metabolism indicators were reduced. In summary, we concluded that NH3 enhanced inflammation and disrupted glucose metabolism, and increased the expression of HSPs and inflammatory factors. In addition, the sensitivity of neutrophils to exogenous stimuli was diminished. This information can not only be used to evaluate the damage of NH3-spiked neutrophils to chickens, but also provide clues for human health pathophysiology caused by excess NH3, providing valuable information for NH3 risk management.

Agrochemical Mixtures and Amphibians: The Combined Effects of Pesticides and Fertilizer on Stress, Acetylcholinesterase Activity, and Bioaccumulation in a Terrestrial Environment.

Tank mixtures are popular within the agricultural community because they are time- and cost-effective, but field applications leave nontarget organisms at risk of exposure. We explored the effects of a common herbicide (atrazine and alachlor) and fertilizer (urea) tank mixture on juvenile frog corticosterone stress levels, acetylcholinesterase (AChE) activity, and pesticide bioaccumulation. Single agrochemical or tank mixtures were applied to terrestrial microcosms, and then individual Southern leopard frog (Lithobates sphenocephala) juveniles were added to microcosms for an 8-h exposure. Afterward, frogs were transferred to aquatic microcosms for 1 h to monitor corticosterone prior to euthanasia, brain tissues were excised to evaluate AChE, and tissue homogenates were analyzed for pesticide bioconcentation with gas chromatography-mass spectrometry. Atrazine significantly increased corticosterone in frogs, particularly when combined with alachlor and urea. Atrazine increased AChE and urea decreased AChE, although no interactive effects of chemical combinations were discernible. Relative to their individual treatments, the complete tank mixture with all 3 agrochemicals resulted in 64% greater bioconcentration of atrazine and 54% greater bioconcentration of alachlor in frog tissues. Our results suggest that agrochemical mixtures as well as their active ingredients can lead to altered stress levels and impaired physiological responses in amphibians. An improved understanding of the effects of co-exposure to environmental contaminants in amphibians is important in assessing the ecological risks these compounds pose. Environ Toxicol Chem 2019;9999:1-10. © 2019 SETAC.

Cadmium in plants: uptake, toxicity, and its interactions with selenium fertilizers.

Cd is the third major contaminant of greatest hazard to the environment after mercury and lead and is considered as the only metal that poses health risks to both humans and animals at plant tissue concentrations that are generally not phytotoxic. Cd accumulation in plant shoots depends on Cd entry through the roots, sequestration within root vacuoles, translocation in the xylem and phloem, and Cd dilution within the plant shoot throughout its growth. Several metal transporters, processes, and channels are involved from the first step of Cd reaching the root cells and until its final accumulation in the edible parts of the plant. It is hard to demonstrate one step as the pivotal factor to decide the Cd tolerance or accumulation ability of plants since the role of a specific transporter/process varies among plant species and even cultivars. In this review, we discuss the sources of Cd pollutants, Cd toxicity to plants, and mechanisms of Cd uptake and redistribution in plant tissues. The metal transporters involved in Cd transport within plant tissues are also discussed and how their manipulation can control Cd uptake and/or translocation. Finally, we discuss the beneficial effects of Se on plants under Cd stress, and how it can minimize or mitigate Cd toxicity in plants.

Multivariate linear regression model for source apportionment and health risk assessment of heavy metals from different environmental media.

The study evaluated source apportionment of heavy metals in vegetable samples from the potential sources of fertilizer, water and soil samples collected along the Changjiang River delta in China. The results showed that 25.72% of vegetable samples (Brassica chinensis L.) containing Pb, and Cd, Cu, Hg and Zn at relatively serious levels were from soil. Combined with principle component analysis (PCA) and cluster analysis (CA), the results of the spatial distribution of heavy metals in different environmental media indicated that fertilizer, water and soil were the main sources of heavy metals in vegetables. The results of multivariate linear regression (MLR) using partition indexes (P) showed that fertilizer contributed to 38.5%, 40.56%, 46.01%, 53.34% and 65.25% of As, Cd, Cu, Pb and Zn contents in vegetables, respectively. In contrast, 44.58% of As, 32.57% of Hg and 32.83% of Pb in vegetables came from soil and 42.78% of Cd and 66.97% of Hg contents in vegetables came from the irrigation water. The results of PCA and CA verified that MLR using P was suitable for determining source apportionment in a vegetable. A health risk assessment was performed; As, Cd and Pb contributed to more than 75% of the total hazard quotient (THQ) values and total carcinogenic risk values (Risktotal) for adults and children through oral ingestion. More than 70% of the estimated THQ and Risktotal is contributed by water and fertilizer. Therefore, it is necessary to increase efforts in screening limits/levels of heavy metals in fertilizer and irrigation water and prioritize appropriate pollution management strategies.

Effects of different vermicompost extracts of palm oil mill effluent and palm-pressed fiber mixture on seed germination of mung bean and its relative toxicity.

Several treatment technologies are available for the treatment of palm oil mill wastes. Vermicomposting is widely recognized as efficient, eco-friendly methods for converting organic waste materials to valuable products. This study evaluates the effect of different vermicompost extracts obtained from palm oil mill effluent (POME) and palm-pressed fiber (PPF) mixtures on the germination, growth, relative toxicity, and photosynthetic pigments of mung beans (Vigna radiata) plant. POME contains valuable nutrients and can be used as a liquid fertilizer for fertigation. Mung bean seeds were sown in petri dishes irrigated with different dilutions of vermicomposted POME-PPF extracts, namely 50, 60, and 70% at varying dilutions. Results showed that at lower dilutions, the vermicompost extracts showed favorable effects on seed germination, seedling growth, and total chlorophyll content in mung bean seedlings, but at higher dilutions, they showed inhibitory effects. The carotenoid contents also decreased with increased dilutions of POME-PPF. This study recommends that the extracts could serve as a good source of fertilizer for the germination and growth enhancement of mung bean seedlings at the recommended dilutions.

Air pollution and risk of hospitalization for epilepsy: the role of farm use of nitrogen fertilizers and emissions of the agricultural air pollutant, nitrous oxide / Poluição do ar e risco de hospitalização por epilepsia: o papel do uso agrícola de fertilizantes nitrogenados e as emissões de poluente atmosférico agrícola, óxido nitroso

ABSTRACT The link between various air pollutants and hospitalization for epilepsy has come under scrutiny. We have proposed that exposure to air pollution and specifically the pervasive agricultural air pollutant and greenhouse gas, nitrous oxide (N2O), may provoke susceptibility to neurodevelopmental disorders. Evidence supports a role of N2O exposure in reducing epileptiform seizure activity, while withdrawal from the drug has been shown to induce seizure-like activity. Therefore, we show here that the statewide use of anthropogenic nitrogen fertilizers (the most recognized causal contributor to environmental N2O burden) is significantly negatively associated with hospitalization for epilepsy in all three pre-specified hospitalization categories, even after multiple pollutant comparison correction (p<.007), while the other identified pollutants were not consistently statistically significantly associated with hospitalization for epilepsy. We discuss potential neurological mechanisms underpinning this association between air pollutants associated with farm use of anthropogenic nitrogen fertilizers and hospitalization for epilepsy.

RESUMO A ligação entre vários poluentes do ar e a hospitalização por epilepsia tem sido examinada. Propusemos que a exposição à poluição do ar, especificamente ao poluente atmosférico generalizado e ao gás de efeito estufa, o óxido nitroso (N2O), poderiam fomentar a susceptibilidade a distúrbios do desenvolvimento neurológico. A evidência apoia o papel da exposição ao N2O na redução da atividade convulsiva epileptiforme, enquanto mostra que a retirada do fármaco induz atividade pseudo-convulsiva. Portanto, mostramos aqui que o uso a nível estatal de fertilizantes nitrogenados antropogênicos (o agente causal mais reconhecido para a carga ambiental de N2O) está significativa e negativamente associado à hospitalização por epilepsia nas três categorias de hospitalização pré-especificadas, mesmo após a correção de comparação de poluentes múltiplos (p <0,007 ), enquanto os outros poluentes identificados não foram consistentemente associados de forma estatística com a hospitalização por epilepsia. Discutimos possíveis mecanismos neurológicos subjacentes a esta associação entre poluentes atmosféricos associados ao uso agrícola de fertilizantes nitrogenados antropogênicos, e hospitalização por epilepsia.

Assessment of oxidative stress and activities of antioxidant enzymes depicts the negative systemic effect of iron-containing fertilizers and plant phenolic compounds in the desert locust.

For herbivore insects, digesting can be somewhat challenging, as the defense mechanisms evolved by plants, including the release of phenolics like the non-protein amino acid L-3,4-dihydroxyphenylalanine (L-DOPA), can cause fitness costs. In addition, industrial and agricultural activities have elevated the amounts of iron that can be found in nature and more particularly FeSO4 that is used as fertilizer. Traces of iron can enhance the auto-oxidation of L-DOPA, in turn, generating reactive oxygen species (ROS) and consequently oxidative stress in insects. We examined the effects of the ion Fe2+ (as FeSO4) and L-DOPA on fifth instars of the desert locust Schistocerca gregaria. We measured the level of oxidative damage occurring to macromolecules (proteins and lipids) from midgut and thoracic tissues and assessed the activities of responsive antioxidant enzymes. Injected L-DOPA and redox-active metal iron generated ROS which caused oxidative damages to proteins and lipids to S. gregaria. The protein carbonyls and lipid peroxides present in tissue homogenates were elevated in treated insects. No synergism was observed when L-DOPA was co-injected with Fe2+. K m values of superoxide dismutase (SOD), glutathione reductase (GR), and glutathione peroxidase (GPx) were 4.3, 2.6, and 4.0 mM in thoracic muscles and 5.00, 2.43, and 1.66 mM in whole midgut for SOD, GR, and GPx, respectively, and 8.3 and 3.43 M for catalase (CAT) in the two tissues, respectively. These results suggest higher affinities of GPx and CAT to H2O2 in midgut than in muscles. The time-course changes in activities of antioxidant enzymes and amounts of protein carbonyls and lipid peroxides showed fluctuating patterns, suggesting complex interactions among macromolecules, L-DOPA and FeSO4, and their degradation products. Our results demonstrated the stressful effects of L-DOPA and FeSO4, proving that iron-containing fertilizers are pollutants that can strongly affect S. gregaria.

Rheumatoid Arthritis in Agricultural Health Study Spouses: Associations with Pesticides and Other Farm Exposures.

BACKGROUND: Farming has been associated with rheumatoid arthritis (RA), but the role of pesticides is not known. OBJECTIVES: We examined associations between RA and pesticides or other agricultural exposures among female spouses of licensed pesticide applicators in the Agricultural Health Study. METHODS: Women were enrolled between 1993 and 1997 and followed through 2010. Cases (n = 275 total, 132 incident), confirmed by a physician or by self-reported use of disease modifying antirheumatic drugs, were compared with noncases (n = 24,018). Odds ratios (OR) and 95% confidence intervals (CI) were estimated using logistic regression models adjusted for age, state, and smoking pack-years. RESULTS: Overall, women with RA were somewhat more likely to have reported lifetime use of any specific pesticide versus no pesticides (OR = 1.4; 95% CI: 1.0, 1.6). Of the 15 pesticides examined, maneb/mancozeb (OR = 3.3; 95% CI: 1.5, 7.1) and glyphosate (OR = 1.4; 95% CI: 1.0, 2.1) were associated with incident RA compared with no pesticide use. An elevated, but non-statistically significant association with incident RA was seen for DDT (OR = 1.9; 95% CI: 0.97, 3.6). Incident RA was also associated with the application of chemical fertilizers (OR = 1.7; 95% CI: 1.1, 2.7) and cleaning with solvents (OR = 1.6; 95% CI: 1.1, 2.4), but inversely associated with lifetime livestock exposure as a child and adult (OR = 0.48; 95% CI: 0.24, 0.97) compared with no livestock exposure. CONCLUSIONS: Our results suggest that specific agricultural pesticides, solvents, and chemical fertilizers may increase the risk of RA in women, while exposures involving animal contact may be protective. Citation: Parks CG, Hoppin JA, De Roos AJ, Costenbader KH, Alavanja MC, Sandler DP. 2016. Rheumatoid arthritis in Agricultural Health Study spouses: associations with pesticides and other farm exposures. Environ Health Perspect 124:1728-1734; http://dx.doi.org/10.1289/EHP129.

A study update of mortality in workers at a phosphate fertilizer production facility.

OBJECTIVE: To evaluate the mortality experience among 3,199 workers employed 1951-1976 at a phosphate fertilizer production plant in central Florida with follow-up through 2011. METHODS: Cause-specific standardized mortality ratios (SMRs) for the full cohort were calculated with the U.S. population as referent. Lung cancer and leukemia risks were further analyzed using conditional logistic regression. RESULTS: The mortality due to all-causes (SMR = 1.07, 95% confidence interval [CI] 1.02-1.13, observed deaths [n] = 1,473), all-cancers (SMR = 1.16, 95%CI 1.06-1.28, n = 431), and a priori outcomes of interests including lung cancer (SMR = 1.32, 95%CI = 1.13-1.53, n = 168) and leukemia (SMR = 1.74, 95%CI = 1.11-2.62, n = 23) were statistically significantly elevated. Regression modeling on employment duration or estimated radiation scores did not show exposure-response relation with lung cancer or leukemia mortality. CONCLUSION: SMR results showed increased lung cancer and leukemia mortality in a full cohort of the phosphate fertilizer production facility. There was, however, no exposure-response relation observed among cases and matched controls.

The severity of iron chlorosis in sensitive plants is related to soil phosphorus levels.

BACKGROUND: Iron (Fe) deficiency chlorosis, a major nutritional problem in plants growing on calcareous soils, is related to the content and reactivity of soil iron oxides and carbonates. The effects of other soil components, however, need elucidation. In this paper we tested the hypothesis that application of high doses of phosphorus (P) to the soil can aggravate Fe chlorosis. RESULTS: Lupin and sorghum were grown on 24 calcareous soils. Leaf chlorophyll concentration (LCC) in lupin decreased with increasing available P/available Fe ratio in the native soil but LCC in sorghum was unaffected by that ratio. Application of P to the soil resulted in significant reduction of LCC and dry weight in lupin. In sorghum, LCC and dry weight were positively affected by P fertilisation for soils poor in available P whereas the opposite effect was generally observed for the P-rich soils. In another experiment where olive plants were pot-grown on two soils during the 2009­2011 period, P fertilisation affected LCC negatively only in 2009 and 2011 and in the soil that was poorer in iron oxides. CONCLUSION: Application of fertiliser P to Fe chlorosis-inducing soils is likely to aggravate this deficiency. However, this effect depends on the plant and the Fe and P statuses of the soil.

Reproduction Symposium: does grazing on biosolids-treated pasture pose a pathophysiological risk associated with increased exposure to endocrine disrupting compounds?

Biosolids (processed human sewage sludge), which contain low individual concentrations of an array of contaminants including heavy metals and organic pollutants such as polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB), and polychlorinated dibenzodioxins/polychlorinated dibenzofurans known to cause physiological disturbances, are increasingly being used as an agricultural fertilizer. This could pose a health threat to both humans and domestic and wild animal species. This review summarizes results of a unique model, used to determine the effects of exposure to mixtures of environmentally relevant concentrations of pollutants, in sheep grazed on biosolids-treated pastures. Pasture treatment results in nonsignificant increases in environmental chemical (EC) concentrations in soil. Whereas EC concentrations were increased in some tissues of both ewes and their fetuses, concentrations were low and variable and deemed to pose little risk to consumer health. Investigation of the effects of gestational EC exposure on fetal development has highlighted a number of issues. The results indicate that gestational EC exposure can adversely affect gonadal development (males and females) and that these effects can impact testicular morphology, ovarian follicle numbers and health, and the transcriptome and proteome in adult animals. In addition, EC exposure can be associated with altered expression of GnRH, GnRH receptors, galanin receptors, and kisspeptin mRNA within the hypothalamus and pituitary gland, gonadotroph populations within the pituitary gland, and regional aberrations in thyroid morphology. In most cases, these anatomical and functional differences do not result in altered peripheral hormone concentrations or reproductive function (e.g., lambing rate), indicating physiological compensation under the conditions tested. Physiological compensation is also suggested from studies that indicate that EC effects may be greater when exposure occurs either before or during gestation compared with EC exposure throughout life. With regard to human and animal health, this body of work questions the concept of safe individual concentration of EC when EC exposure typically occurs as complex mixtures. It suggests that developmental EC exposure may affect many different physiological systems, with some sex-specific differences in EC sensitivity, and that EC effects may be masked under favorable physiological conditions.

New insights on non-B non-C hepatocellular carcinoma in mid Delta Region, Egypt.

PURPOSE: The rate of hepatocellular carcinoma (HCC) is increasing worldwide, including in Egypt. Hepatitis B (HBV) and C (HCV) viruses are major risks. Non-B non-C HCC was reported in some countries. We investigated non-B non-C HCC-independent risk factors and associated profiles in viral hepatitis endemic region. METHODS: In a consecutive series, 281 patients were diagnosed with HCC and received for management, at Tanta University Hospitals, within the past 3 years. Demographic variables and environmental exposures were recorded by direct application of a modified questionnaire. Sera were tested for HCV (antibodies by ELISA and RNA by RT-PCR) and HBV (HBs Ag by ELISA and HBV DNA). Antinuclear antibody, serum copper, and iron were assessed in non-viral HCC. Liver biopsy was performed for HCC diagnosis and grading and liver tissue in all patients by histopathological and immunohistochemical methods to assess HBV and/or HCV etiology. RESULTS: Non-B non-C HCC patients were 13.87% of the total and were associated with multiple risks, predominantly pesticides (100%, p < 0.001) and super phosphate and ammonium sulfate fertilizers (94.87%, p < 0.001) with significant exposure in industry, farming, and residence. Their tumors were mainly solitary, smaller sizes, and of lower alpha-fetoprotein titers. The study showed insignificant increase in prevalence of non-B non-C HCC and had special characters. Multivariate analysis showed significance of pesticides and smoking as independent risks for non-B non-C HCC. CONCLUSIONS: Pesticides and smoking heavy exposure can be considered as primary risks for non-B non-C HCC. Phosphate and ammonium sulfate fertilizers were associations. The study will increase awareness for better prevention and management.

A meta-analysis of the effects of pesticides and fertilizers on survival and growth of amphibians.

The input of agrochemicals has contributed to alteration of community composition in managed and associated natural systems, including amphibian biodiversity. Pesticides and fertilizers negatively affect many amphibian species and can cause mortality and sublethal effects, such as reduced growth and increased susceptibility to disease. However, the effect of pesticides and fertilizers varies among amphibian species. We used meta-analytic techniques to quantify the lethal and sublethal effects of pesticides and fertilizers on amphibians in an effort to review the published work to date and produce generalized conclusions. We found that pesticides and fertilizers had a negative effect on survival of -0.9027 and growth of -0.0737 across all reported amphibian species. We also observed differences between chemical classes in their impact on amphibians: inorganic fertilizers, organophosphates, chloropyridinyl, phosphonoglycines, carbamates, and triazines negatively affected amphibian survival, while organophosphates and phosphonoglycines negatively affected amphibian growth. Our results suggest that pesticides and fertilizers are an important stressor for amphibians in agriculturally dominated systems. Furthermore, certain chemical classes are more likely to harm amphibians. Best management practices in agroecosystems should incorporate amphibian species-specific response to agrochemicals as well as life stage dependent susceptibility to best conserve amphibian biodiversity in these landscapes.

Exposure to pesticides and metal contaminants of fertilizer among tree planters.

In British Columbia, Canada, harvested forests are manually replanted by seasonal workers. The work is known to be physically demanding and ergonomically difficult, and recently, there have been concerns over chemical exposures due to pesticide residues on seedlings, fertilizers (often applied alongside seedlings), and potential metal contamination of these fertilizers. This study aimed to characterize metal and pesticide exposure among a sample of British Columbia tree planters. Between May 2006 and April 2007, exposure measurements were taken from 54 tree planters at five geographically disperse worksites throughout British Columbia. Four worksites were using fertilizer and one was not. Metal concentrations were measured by inductively coupled plasma mass spectrometry on post-shift hand wipes, full-shift personal air sample, bulk soil, seedling root balls, and fertilizer samples. Pesticides were measured on post-shift hand wipes and on bulk seedling samples. Seedling nursery pesticide application records were used to focus pesticide analyses on pesticides known to have been applied to the seedlings used at the study sites. Carbamate pesticides were analyzed by high-performance liquid chromatography/mass spectroscopy and all other pesticides by gas chromatography mass spectrometry. No evidence was found that tree planters who worked with fertilizer were at an elevated risk of exposure to arsenic, lead, cadmium, chromium, and nickel relative to tree planters who did not. Pesticide residues were found on seedlings taken from work sites early in the tree planting season in April 2007. At these worksites, the fungicides chlorothalonil and iprodione were found on the skin of workers at low levels (range 0.37-106.3 ng cm(-2) and 0.48-15.9 ng cm(-2), respectively), providing evidence for exposure potential. Very poor hygiene conditions were observed at all tree planting work sites. Hand washing facilities were not available at work sites and only 5.6% of subjects reported hand washing during the work day, including prior to eating or smoking. Gloves were worn by all subjects but no personal protective equipment programs existed to train workers in the correct use or selection of gloves, and consequentially, many glove choices were inappropriate. The lack of hand washing facilities combined with incorrect glove use could increase the duration of dermal exposure and increase the risk of hand-to-mouth ingestion exposure.