Three experiments were performed to compare the P availability between struvite and the commercial fertilizer monoammonium phosphate (MAP). Experiment 1 evaluated triticale grown in a commercial potting medium and fertilized with struvite and MAP at 0, 56, 112, and 224 kg P₂O₅ ha⁻¹. Struvite was comparable for dry matter (DM) yield (P < 0.01) and resulted in greater concentrations of P (P < 0.005) compared to MAP. Experiment 2 evaluated triticale and oats planted in two soils differing in pH, and fertilized with either struvite or MAP at 0, 56, 112, and 224 kg P₂O₅ ha⁻¹. When oats were grown in acidic soil, struvite provided greater P uptake (P < 0.0001) and concentration of P (P < 0.0001) in the plant compared to MAP. When triticale was grown in acidic soil, struvite provided the greatest DM yield (P < 0.005), P uptake (P < 0.0001), and concentration of P (P < 0.0001) compared to MAP. When triticale and oats were grown in alkaline soil, struvite produced the greatest concentration of P (P < 0.003) compared to MAP for oats. Experiment 3 evaluated corn and alfalfa over a 3-year period planted in alkaline soil and fertilized with either struvite or MAP at 0, 140, and 280 kg P₂O₅ ha⁻¹. In 2006 and 2007, struvite and MAP were comparable for DM yield (P < 0.05) and concentration of P (P < 0.05) in alfalfa. Using MAP resulted in greater P uptake (P < 0.05) all 3 years for alfalfa, and greater DM yields (P < 0.05) and concentrations of P (P < 0.05) in 2008. For corn, MAP produced the greatest DM yield (P < 0.001), P uptake (P < 0.003), and concentration of P (P < 0.001) all 3 years. Struvite was a comparable or superior P fertilizer compared to MAP in acidic soils and inferior to MAP in alkaline soils.

Classification of spectral data has recently drawn more and more attention in environmental and geoscience applications. In the past decade, this attention has been translated into an interest in employing unmixing techniques to retrieve accurate quantitative information suppressed in spectral data. The main task in real applications is to detect potential information regarding the physical and chemical nature of ground targets in different spectral data sources (point field and laboratory spectroscopy, hyperspectral imagery, etc.). Recently, semisupervised classification techniques have been proposed for spectral data by combining ground-truth and laboratory measured spectral signatures and advanced signal processing algorithms based on posterior probability support vector machine and Dempster-Shafer evidence theory. In this paper, the sensitivity of this combined classification method to extract and identify a small amount of settle dust over green vegetation canopy using field spectral data is examined and reported. The results are compared with the performance of selected semisupervised unmixing classification techniques.

High serum concentrations of polychlorinated biphenyls (PCBs) have been reported previously among residents of Anniston, Alabama, where a PCB production facility was located in the past. As the second of two cross-sectional studies of these Anniston residents, the Anniston Community Health Survey: Follow-Up and Dioxin Analyses (ACHS-II) will yield repeated measurements to be used to evaluate changes over time in ortho-PCB concentrations and selected health indicators in study participants. Dioxins, non-ortho PCBs, other chemicals, heavy metals, and a variety of additional clinical tests not previously measured in the original ACHS cohort will be examined in ACHS-II. The follow-up study also incorporates a questionnaire with extended sections on diet and occupational history for a more comprehensive assessment of possible exposure sources. Data collection for ACHS-II from 359 eligible participants took place in 2014, 7 to 9 years after ACHS.

Phytoextraction has been proposed as an alternative remediation technology for heavy metal contamination, and it is well known that chelators may alter the toxicity of heavy metals and the bioavailability in plants. Our previous work demonstrated that an adsorbent-column chromatography can effectively separate melanoidin-like product (MLP) from sugarcane molasses. The aim of this study was to examine the chelating property of MLP and to evaluate the facilitatory influence on the phytoextraction efficiency of Japanese radish. The result showed that MLP binds to all the metal ions examined and the binding capacity of MLP toward Cu²⁺ seems to be the highest among them. The metal detoxification by MLP followed the order of Pb²⁺ > Zn²⁺ > Ni²⁺ > Cu²⁺ > Fe²⁺ > Cd²⁺ > Co²⁺. Furthermore, in the phytoextraction experiment using copper sulfate, the application of MLP accelerated the detoxification of copper and the bioavailability in radish sprouts. Thus, these results suggest that MLP possesses the potential for an accelerator of phytoextraction in the copper-contaminated media.

Spatio-temporal cancer mortality studies in Spain have revealed patterns for some tumours which display a distribution that is similar across the sexes and persists over time. Such characteristics would be common to tumours that shared risk factors, including the chemical soil composition. The objective of the present study is to assess the association between levels of chromium and arsenic in soil and the cancer mortality. This is an ecological cancer mortality study at municipal level, covering 861,440 cancer deaths in 7917 Spanish mainland towns from 1999 to 2008. Chromium and arsenic topsoil levels (partial extraction) were determined by ICP-MS at 13,317 sampling points. To estimate the effect of these concentrations on mortality, we fitted Besag, York and Mollié models, which included, as explanatory variables, each town’s chromium and arsenic soil levels, estimated by kriging. In addition, we also fitted geostatistical-spatial models including sample locations and town centroids (non-aligned data), using the integrated nested Laplace approximation (INLA) and stochastic partial differential equations (SPDE). All results were adjusted for socio-demographic variables and proximity to industrial emissions. The results showed a statistical association in men and women alike, between arsenic soil levels and mortality due to cancers of the stomach, pancreas, lung and brain and non-Hodgkin’s lymphomas (NHL). Among men, an association was observed with cancers of the prostate, buccal cavity and pharynx, oesophagus, colorectal and kidney. Chromium topsoil levels were associated with mortality among women alone, in cancers of the upper gastrointestinal tract, breast and NHL. Our results suggest that chronic exposure arising from low levels of arsenic and chromium in topsoil could be a potential risk factor for developing cancer.

The growing production of beef has resulted in the increased volume of liquid residues generated during slaughtering and processing, known as slaughterhouse wastewater. In an attempt to reduce the organic content of this wastewater, blood has been separated from the water, generating slaughterhouse wastewater from green line slaughter and processing (SHWW in natura). The objective of this study was to determine the physical, chemical, and toxicological characteristics of SHWW in natura collected from a bovine slaughterhouse and locker. The results obtained from this characterization showed a high concentration of solids, total volatile acids, alkalinity, macro and micro nutrients, and organic matter (BOD₅ ²⁰°C, COD, and DOC). The effluent presented acute toxicity to the test-organisms P. putida, E. coli, and D. similis, and chronic toxicity to the test-organisms C. silvestri, C. dúbia, E. coli, P putida, and P. subcaptata. Based on the ecotoxicological tests, it was concluded that the compounds of the SHWW in natura were more toxic to microcrustaceans and algae than to bacteria.

Sulfide, found in some wastewaters and industrial off-gases, is a toxic and highly corrosive pollutant, especially in wastewater applications. Sulfide removal was studied in a new sulfide-oxidizing reactor (External Silicone Membrane Reactor—ESMR) that employs a tubular silicone rubber membrane for micro-aeration. The chemical and biological sulfide oxidation at pH 8.0, 9.0, and 10.0 were investigated. The applied velocity (V ₛ) in the membrane was also investigated as a system control parameter. The local overall mass transfer coefficient (R) was estimated for the tubular silicone rubber membrane and had an average value of 0.153 m.h⁻¹. Oxygen mass transfer was found to not be influenced by the applied velocity. The sulfide oxidation to sulfate could be partially avoided and the biotic tests showed larger sulfur aggregates deposited in the silicone membrane, which could easily be washed away upon flushing. By contrast, colloidal sulfur formation observed in the chemical oxidation assays was harder to separate from the liquid phase. This study reveals that the ESMR is a suitable reactor design to promote partial sulfide oxidation because it provides an adequate oxygen supply with minimized aeration costs.

In the last 40 years of the twentieth century, as a result of the growth in the exploitation and industrial processing of sulphur, the northern part of the Sandomierz Basin was one of the most polluted areas of Poland. Forests growing in this region, predominantly the Scots pine, offered an opportunity to analyse the degradation of the environment during that period using the dendrochronological method. The study was based on 814 samples, taken from 53 research surfaces belonging to nine linear transects. The investigations demonstrated that the highest reduction in growth occurred during the years 1970–1990. After that period, a considerable improvement in the condition of the pine trees was observed in most of the research plots. The spatial schedule of the trees with reductions reveals a clear relationship with the distance from the emitter i.e. the reductions were significantly lower in more distant sites. A distinct weakening of the trees is also indicated by missing rings, recorded in the years: 1964, 1974, 1978, 1979, 1980, 1985, 1990, and 2002. A definite impact on the condition of the tree stands was also due to the cone of depression around the Jeziórko mine, the post-flotation landfills, as well as pollution on a regional scale.

The concentration partitioning between the sediment particle and the interstitial water phase plays an important role in controlling the toxicity of heavy metals in aquatic systems. The aim of this study was to assess the sediment quality in a polluted area of the Ziya River, Northern China. The contamination potential and bioavailability of six metals were determined from the concentrations of total metals and the bioavailable fractions. The results showed that the concentrations of Cr, Cu, Ni, Zn, and Pb exceeded the probable effect concentration at several sites. The high geoaccumulation indices showed that the sediments were seriously contaminated by Cd. The ratio of acid-volatile sulfide (AVS) to simultaneously extracted metal (SEM) was higher than 1, which indicated that the availability of metals in sediments was low. The risk assessment of interstitial waters confirmed that there was little chance of release of metals associated with acid-volatile sulfide into the water column. Values of the interstitial water criteria toxicity unit indicated that none of the concentrations of the studied metals exceeded the corresponding water quality thresholds of the US Environmental Protection Agency. Positive matrix factorization showed that the major sources of metals were related to anthropogenic activities. Further, if assessments are based on total heavy metal concentrations, the toxicity of heavy metals in sediment may be overestimated.

Benzo[a]pyrene (B[a]P) is an environmental toxicant and endocrine disruptor. Therefore, the aim of the present study was to investigate the toxicity of B[a]P in testis of rats and also to study the role of silymarin and thymoquinone (TQ) as natural antioxidants in the alleviation of such toxicity. Data of the present study showed that levels of testosterone, estrogen and progesterone were significantly decreased after treatment of rats with B[a]P. In addition, B[a]P caused downregulation of the expressions of steroidogenic enzymes including CYP17A1 and CP19A1, and decreased the activity of 17-β hydroxysteroid dehydrogenase (17β-HSD). Moreover, B[a]P decreased the activities of antioxidant enzymes including catalase (CAT), glutathione peroxidase (GPX) and superoxide dismutase (SOD), and significantly increased free radicals levels in testis of male rats. However, pretreatment of rats with silymarin prior to administration of B[a]P was found to restore the level of free radicals, antioxidant status, and activities of steroidogenic enzymes to their normal levels in testicular tissues. Moreover, histopathological finding showed that silymarin recovered the abnormalities occurred in tubules caused by B[a] P in testis of rats. On the other hand, TQ showed pro-oxidant effects and did not ameliorate the toxic effects of B[a] P on the testicular tissue since it decreased antioxidant enzymes activities and inhibited the protein expression of CYP11A1 and CYP21A2 compared to control rats. Moreover, TQ decreased the levels of testosterone, estrogen, and progesterone either in the presence or absence of B[a]P. It is concluded that B[a]P decreased testosterone levels, inhibited antioxidant enzymes activities, caused downregulation of CYP isozymes involved in steroidogenesis, and increased free radical levels in testis. Moreover, silymarin was more effective than TQ in restoring organism health and alleviating the deleterious effects caused by B[a]P in the testis of rats. Due to its negative impact, it is highly recommended to limit the use of TQ as a dietary supplement since millions of people in the Middle East are using it to improve their health.