Environmental contaminants are gaining more attention in the livestock sector lately due to their harmful effects on productivity and fertility of livestock. Recent research indicates that many domestic ruminants are becoming subfertile/infertile due to confounding reasons associated with management. Contaminants like metals, metalloids, herbicides, pesticides, insecticides, chemicals, or natural contaminants are present everywhere in day to day life and are becoming a threat to the livestock. Studies on a broad-spectrum of animals suggest that high doses of acute or low doses of chronic exposure to the contaminants lead to disruption of multi-organs/systems including reproductive function. The lowered reproductive efficiency in animals is attributed to the endocrine disruptor activities of the environmental contaminants on the gonads, affecting gametogenesis and steroidogenesis. In vitro studies on testicular cells and the semen suggest that spermatozoa are more susceptible to damage by environmental contaminants. The quality of the semen happens to be a critical factor in the livestock industry. Contaminants affecting gametogenesis and steroidogenesis may lead to devastating consequences to the livestock reproduction, and thus the production. However, there is a lack of collective data on the effect of such environmental contaminants on the fertility of male domestic ruminants. This review discusses the studies related to the impact of environmental contaminants on male fertility in large (bull and buffalo) and small (sheep and goat) ruminants by focusing on the underlying molecular interactions between the contaminants and gonads.

Solid-state fermentation (SSF) of ammoniated corn straw was used to produce feed protein, followed by a toxicological assessment of the fermentation product. Results showed that through ammonification at 35 °C for 9 days and the subsequent SSF by the two fungi Penicillium sp. and Torula allii at 30 °C for 5 days, the contents of real protein and crude protein of the corn straw reached 29.66% and 35.41%, respectively. Toxicological assessment in mice showed that there were no significant differences (P > 0.05) for micronucleated polychromatic erythrocytes (Mn-PCEs) and sperm abnormality between dose groups and the control group. Malondialdehyde (MDA) levels and activities of superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) also showed no significant difference (P > 0.05) between tissues (heart, liver, spleen, stomach, kidney, and brain), which indicates that the fermentation product did not induce toxic effects and is safe to use as ruminant feed.

Wastes from the Pacara Earpod tree (Enterolobium contortisilquum) and Ironwood (Caesalpinia leiostachya) seeds were studied as biosorbents for the removal of basic fuchsin from waters. Both biosorbents were prepared and characterized by different analytical methods. The characterization data showed that both materials were mainly composed of lignin, cellulose, and hemicellulose. Both biosorbents exhibited roughened surfaces and surface functional groups such as C-H, C=O, C=C, C-O, C-N, and OH bonds. Furthermore, the XRD pattern shows an amorphous phase with a wide peak from 10 to 30° due to the lignin. In terms of dosage and pH, the use of 1 g L⁻¹ and 9.0, respectively, is recommended. The initial concentrations for the biosorption kinetics ranged from 50 to 500 mg L⁻¹, where the Pacara ear and the Ironwood reached an adsorption capacity of 145.62 and 100.743 mg g⁻¹ for the 500 mg L⁻¹. The pseudo-second-order was found to be the proper model for describing biosorption of basic fuchsin onto Pacara Earpod tree and Ironwood, respectively. For the isotherm experiments, the maximum experimental biosorption capacity was found to be 166.858 and 110.317 mg g⁻¹ for the Pacara Earpod and Ironwood for the initial concentration of 500 mg L⁻¹ at 328 K. The Langmuir and the Tóth models were the best for representing the equilibrium curves for the basic fuchsin on the Pacara Earpod and the Ironwood, respectively. Maximum adsorption capacities of 177.084 mg g⁻¹ and 136.526 mg g⁻¹ were achieved for the Pacara Earpod tree and Ironwood, respectively. The biosorption process was spontaneous, endothermic, and favorable for both biosorbents. The biosorbents were also applied for coloration removal of simulated textile effluents, reaching 66% and 54% for the Pacara Earpod and Ironwood, respectively. For the final application, the materials were used in fixed-bed biosorption, with an initial concentration of 200 mg L⁻¹, reaching breakthrough times of 710 and 415 min, leading to biosorption capacities of the column of 124.5 and 76.5 mg g⁻¹, for the Pacara Earpod and Ironwood, respectively.

Given the recent extensive synthesis and application of ionic liquids (ILs), finding a sensitive and visual indicator to provide a fast-initial risk assessment of IL use has become a pressing issue. In this study, we verified that the phototaxis of Chlamydomonas reinhardtii is a valid indicator of the environmental risk associated with chiral ILs L-(+)- and D-(−)-1-butyl-3-methylimidazolium lactate (BMIM L). Briefly, C. reinhardtii was exposed to a 4000-lx side light source for varying lengths of time. Following the allotted exposure time, the algae aggregation was photographed, and then quantitative analysis was conducted using Image-J software to obtain the corresponding relationship between IL stimulation and C. reinhardtii phototaxis. The gray areas from each treatment were measured and the percentage was calculated. After 16 h of side lighting, for control, the percentage of gray areas was − 22%, while for L-(+)- and D-(−)- BMIM L were 17% and 33%, respectively. Then, after 8 h of darkness, where D-(−)-BMIM L and the control showed the positive phototaxis, but the L-(+)-BMIM L-treated group showed virtually no change. This phenomenon is consistent with excessive production of reactive oxygen species (ROS). Moreover, atomic force microscope (AFM) results indicated distinct aggregation between D-(−)- and L-(+)-BMIM L, which caused changes in cell permeability that induced a change in ROS transfer. Furthermore, relationship between phototaxis and changes in cell ultrastructure and photosynthetic efficiency was also investigated. This work demonstrates the potential of phototaxis to serve as a sensitive, convenient, and cost effective qualitative assessment of ILs’ toxic impact, with the understanding that quantitative evaluation requires further improvement.

Arsenic is a major environmental toxicant of concern, affecting both female and male reproductive systems. The present study was conducted to investigate the toxic effects of arsenic on semen quality and reproductive hormones of Teddy bucks, an important domestic species in regions of Pakistan. In addition to arsenic, vitamin C was fed to a subset of animals to determine if there were ameliorative effects on reproductive parameters. Sixteen adult Teddy bucks were randomly divided into four experimental groups: A (control), B (arsenic 5 mg/kg BW/day orally), and C (arsenic 5 mg/kg BW/day plus vitamin C of an oral dose of 200 mg/kg BW/day). The animals in experimental group D were given only vitamin C (oral dose of 200 mg/kg BW/day). Animals were fed treated food once a day for 12 weeks. Semen quality parameters (volume, motility, count, sperm morphology, live dead ratio, sperm membrane integrity, and sperm DNA integrity) of bucks from each experimental group were evaluated on a weekly basis. Hematology and the level of arsenic in the blood were assessed every 2 weeks. Serum was collected fortnightly to measure reproductive and stress hormones (testosterone, luteinizing hormone, follicle-stimulating hormones, and cortisol). At the end of the study, all the animals were slaughtered, and the testes of all the animals were collected and evaluated for histopathology. Semen parameters in arsenic-treated bucks were significantly reduced (p < 0.05) compared with controls. Moreover, the levels of male hormones (testosterone, luteinizing hormone, and follicle-stimulating hormone) were significantly decreased in arsenic-treated animals, while cortisol was significantly increased with arsenic exposure. The histopathological lesions in the testes were present in the form of the loss of germinal epithelium and atrophy of Leydig cells. Supplementation of vitamin C however ameliorated the adverse effects of arsenic on semen quality and hormones. The histopathological lesions were also ameliorated due to vitamin C treatment. This study demonstrates that arsenic can adversely affect reproductive endpoints in Teddy goat bucks and supports the hypothesis that vitamin C is an effective treatment in arsenic-induced toxicosis. This study has high significance for Pakistan, as water contaminated with arsenic is a top health concern and is a recurring issue for both domestic animals and humans.

As a new and efficient selective pre-emergence herbicide, flurochloridone (FLC) has been widely promoted in recent years but readily results in residues in nature. As the primary producers and restorers of the water environment, aquatic plants are at risk of FLC exposure. In the present research, we studied the phytotoxicity of FLC in Lemna minor and Ceratophyllum demersum. The physiological and growth responses of these two aquatic plants exposed to different concentrations of FLC (0, 20, 100, 300, 1000, and 2000 μg/L) were measured. The results showed that FLC (≥ 20 μg/L) could cause serious photosynthesis pigment damage and bleaching in C. demersum and L. minor. Significant oxidative damage was observed in L. minor at 20 μg/L FLC, while there was no severe oxidative damage in C. demersum. At 100–300 μg/L FLC, peroxidase (POD) and superoxide dismutase (SOD) were activated to scavenge free radicals in L. minor, while POD acted as a protective enzyme in C. demersum. At higher concentrations of FLC (≥ 1000–2000 μg/L), L. minor reached less than healthy stability through the regulation of the antioxidant enzyme system and the chlorophyll a/b value. POD, SOD, and protein content returned to normal levels, and the growth parameters increased. However, in C. demersum, the enzymes POD and SOD and soluble protein were damaged, and oxidative stress reached the highest level at 1000–2000 μg/L FLC. Taken together, our results suggested that when treated with FLC, L. minor was more sensitive at lower doses (20 μg/L) and more adaptive at higher doses (1000–2000 μg/L) than C. demersum.

Investigation of water pollution–economic growth nexus is an important component for the sustainable development of eco-environment and socio-economy. This study combined the improved Grey relational degree (GRD) model with the environmental Kuznets curve (EKC) to quantitatively and qualitatively investigate the relationships between water pollution and economic growth in Nansi Lake catchment (Jining, Zaozhuang, and Heze) under the context of the Five-Year Plan in Shandong. Results showed that the relational degree of industrial wastewater and economic growth was Heze (0.652) > Zaozhuang (0.581) > Jining (0.538), and of domestic wastewater and economic growth was Jining (0.722) > Heze (0.721) > Zaozhuang (0.650). Meanwhile, the EKC of industrial wastewater rose and then declined, whereas that of domestic wastewater increased upwards. Overall, coordinated development had been gradually obtained between industrial wastewater emissions and economic growth. And, uncoordinated development between domestic wastewater emissions and economic growth still existed, indeed, in recent years it had intensified. Further, domestic wastewater emissions continue to rise, to the point where they now constitute one of the main sources of water pollution in Nansi Lake catchment. Results of this study indicated that combining the improved GRD model with the EKC provides a new approach to comprehensive investigation of the water pollution–economic growth nexus from a qualitative and quantitative perspective.

A large volume (more than 4.0 million m³) of treated construction and demolition waste (CDW) is planned to be used in the construction of the Xi’an-Xianyang north loop line freeway in West China. These CDW were preliminarily separated into broken concretes, bricks, and porcelains in the treatment plants. In this study, a total of 190 CDW samples including 80 concretes, 80 bricks, 20 porcelains, and 10 mixed samples were collected from five treatment plants. Five farmland soil samples near treatment plants were collected as controls. The contents of 10 elements including cadmium (Cd), arsenic (As), copper (Cu), nickel (Ni), zinc (Zn), chromium (Cr), lead (Pb), manganese (Mn), silver (Ag), and mercury (Hg) in these samples were measured. The contents of 8 elements (Cu, Ni, Zn, Cr, Pb, Mn, Ag, and Hg) in all CDW samples were qualified for the third-level criterion of the Standard of Soil Environment (GB15618-2008). However, Cd contents in 37 concretes, 34 bricks, 6 porcelain samples, and 4 mixed CDW samples exceeded the national third-level standards (1 mg/kg) in GB15618-2008. And As contents in 28 concretes, 21 bricks, 5 porcelain samples, and 3 mixed CDW samples were higher than the national third-level standards (40 mg/kg). The total exceeding standard rates (ESRs) of Cd and As were 42.6% and 30%, respectively. The leaching tests for Cd and As were also done due to their higher ESRs. The results showed that the release amounts (μg/kg) of Cd and As from CDW were increased with increasing liquid to solid ratio (0.4–10 l/kg) but decreased with increasing pH (4–7). The leached concentrations of Cd and As from four types of CDW samples were both in a descending order: brick, mixed materials, concrete, and porcelain. The measured concentrations (μg/L) of Cd and As in leachate were all lower than second-grade criteria of Standard for Groundwater Quality (GB3838-2002). By comparing the leached concentrations of Cd and As with the value in European criteria (EU Council Decision 2003/33/EC) for hazardous wastes, all the CDW samples should be classified as inert or non-hazardous wastes. Thus, it could be concluded that heavy metals in these CDW would not pollute surrounding soil, surface water, and groundwater environment when applied in freeway construction.

Atrazine is currently one of the most used herbicides worldwide. We tested the possible effect of the widely used herbicide atrazine on the endocrine control of ovarian growth exerted by the neurohormones secreted at the eyestalk of the estuarine crab Neohelice granulata. For this, both in vivo and in vitro assays were carried out. The in vivo assay comprised the exposure for 1 month to 3 mg/L of a commercial formulation containing 90% of atrazine as active ingredient (Gesaprim 90 WDG®, Syngenta) on three categories of females: intact, ablated of one eyestalk, and ablated of both eyestalks. At the end of the assay, only the intact females showed a significant (p < 0.05) decrease in both content of vitellogenic ovarian proteins and proportion of vitellogenic oocytes, compared to a concurrent control. The results of the in vitro incubation of ovarian pieces with the eventual addition to the incubation medium of eyestalk tissue and/or atrazine at 3 mg/L showed a significant (p < 0.05) decrease in the proportion of vitellogenic oocytes only when atrazine and eyestalk tissue were added. Taken together, these results strongly suggest that the assayed atrazine formulation may act as an endocrine disruptor at the eyestalk level, by altering the normal secretion of some eyestalk hormone, therefore inhibiting ovarian growth.