This study determined the subcellular distribution, chemical forms, and effects of metal homeostasis of excess Cd in Cladophora rupestris. Biosorption data were analyzed with Langmuir and Freundlich adsorption models and kinetic equations. Results showed that C. rupestris can accumulate Cd. Cd mainly localized in the cell wall and debris (42.8–68.2%) of C. rupestris, followed by the soluble fraction (22.1–38.4%) observed in C. rupestris. A large quantity of Cd ions existed as insoluble CdHPO₄ complexed with organic acids, Cd(H₂PO₄)₂, Cd-phosphate complexes (FHAC) (43.2–56.0%), and pectate and protein-integrated Cd (FNₐCₗ) (30.8–43.2%). The adsorption data were well fitted by the Freundlich model (R² = 0.933) and could be described by the pseudo-second-order reaction rate (R² = 0.997) and Elovich (R² = 0.972) equations. Related parameters indicated that Cd adsorption by C. rupestris is a heterogeneous diffusion. Cd promoted Ca and Zn uptake by C. rupestris. Cu, Fe, Mn, and Mg adsorption was promoted by low Cd concentrations and inhibited by high Cd concentrations. Results suggested that cell wall sequestration, vacuolar compartmentalization, and chemical morphological transformation are important mechanisms of Cd stress tolerance by C. rupestris. This study suggests that C. rupestris has bioremediation potential of Cd.

Gadfly petrels (Pterodroma spp.) are one of the most threatened and poorly studied seabird groups, and as marine predators, are exposed to biomagnified and bioaccumulated chemical pollutants from their prey. We quantified trace element concentrations in breast feathers of seven petrel species that breed in the southern hemisphere to quantify current concentrations. Selenium (Se) concentrations were significantly lower in chicks than adults; this was not observed for zinc (Zn) or lead (Pb). Overall, the species examined here exhibited similar concentrations of Se, with Pb and Zn concentrations more variable among species. The mean Se concentration in adult birds exceeded those thought to be potentially deleterious, and three species had concentrations that were above the assumed threshold for Pb toxicity. Further investigation of potentially toxic trace elements in gadfly petrels is warranted.

Few studies have investigated the acute exacerbations of chronic obstructive pulmonary disease (AECOPD)-associated attributable burden under exposure to high levels of air pollution among Asians. Data on hospitalization for AECOPD, air pollution and meteorological factors from 1 January 2013 to 31 December 2016 were collected in Shijiazhuang, China. We used a Poisson generalized linear regression model combined with a distributed lag nonlinear model (DLNM) to evaluate the relative cumulative risk for a lag of 0–7 days and examined the potential effect modifications by age and sex via stratification analyses, controlling for long-term trends, seasonal patterns, meteorological factors, and other possible confounders. Then, we computed hospitalization percentages attributable to air pollutants. The AECOPD-associated relative cumulative risks for PM₂.₅, PM₁₀, NO₂, SO₂, and CO for a lag of 0–7 days were significantly positively correlated with hospitalization. The associations were stronger in females and retired patients. The NO₂ Cum RR of AECOPD admission was the greatest. A 10μg/m³ increase in daily NO₂ concentration was associated with 6.7% and 5.7% increases in COPD hospitalizations in the retired and female groups, respectively. The results showed that 13%, 9.4%, 1.7%, 9.7%, and 8.8% of AECOPD hospitalizations were attributable to exposure to PM₂.₅, PM₁₀, SO₂, NO₂, and CO, respectively. If the air pollutant concentration was reduced to the 24-h average grade II levels of NAAQS of China, the AECOPD attributable percentage for PM₂.₅ and PM₁₀ would decrease by 80%. The air pollutants PM₂.₅, PM₁₀, SO₂, NO₂, and CO were significantly relevant to AECOPD-associated hospitalization. The associations differed by individual characteristics. The retired and female populations were highly vulnerable.

On page 6156, “Regeneration of the MNPs for Cu(II) and Cr(VI) adsorption was conducted by using 0.1 mol/L HCl solution and NaOH solution as eluents, respectively” should read “Regeneration of the MNPs for Cu(II) and Cr(VI) adsorption was conducted by using 1.0 mol/L HCl solution and NaOH solution as eluents, respectively”.

Difenoconazole is a fungicide extensively used in agriculture. The aim of this study was to evaluate the effects of difenoconazole fungicide on the sperm quality of rats. Wistar rats were divided into four groups: control and exposed to 5 (D5), 10 (D10), or 50 mg⁻¹ kg bw⁻¹day (D50) of difenoconazole for 30 days, by gavage. Classical sperm parameters and surface-enhanced Raman scattering (SERS) were performed. Progressive motility, acrosomal integrity, and percentage of morphologically normal spermatozoa were reduced in the D10 and D50 groups in comparison with the control group. Sperm viability was reduced only in the D50 group. Sperm number in the testis and caput/corpus epididymis and daily sperm production were reduced in the three exposed groups. SERS measurements showed changes in the spectra of spermatozoa from D50 group, suggesting DNA damage. In addition, machine learning (ML) methods were used to evaluate the performance of three classification algorithms (artificial neural network—ANN, K-nearest neighbors—K-NN, and support vector machine—SVM) in the identification task of the groups exposed to difenoconazole. The results obtained by ML algorithms were very promising with accuracy ≥ 90% and validated the hypothesis of the exposure to difenoconazole reduces sperm quality. In conclusion, exposure of rats to different doses of the fungicide difenoconazole may impair sperm quality, with a recognizable classification pattern of exposure groups.

The article Does CO₂ emissions–economic growth relationship reveal EKC in developing countries? Evidence from Kazakhstan, written by Fakhri J. Hasanov, Jeyhun I.

To effectively remove phosphate pollution and convectively reuse phosphate resource, straw biochar was firstly functionalized with lanthanum ferrite (LaFeO₃) via four different methods, including one-step co-precipitation (S-C), two-step co-precipitation (B-C), one-step impregnation (S-E), and two-step impregnation (B-E). LaFeO₃/biochar was characterized systematically by a series of characterization methods. The influence of preparation methods, operation conditions on adsorption process, and the regenerability were studied. The products prepared by four methods displayed different physical morphology and chemical analysis proved chemical composition were similar. LaFeO₃/biochar exhibited high adsorption capacity, the pseudo-second-order and Sips models were fitted for the adsorption equilibrium. The LaFeO₃/biochar exhibited outstanding phosphate adsorption performance with pH values ranging from 2.3 to 10.6; La ions release was similarly negligible, when pH value was higher than 5.27. The adsorption mechanism was studied and inferred that La species is the key to adsorption ability. The results obtained provide better understanding of the adsorption phenomena and indicate the available preparation technologies and potential usefulness of LaFeO₃/biochar for removing phosphate pollution. Graphical abstract “.”

The paper investigates the effect of financial development and institutional quality on the environment in South Asia. Other determinants of environmental quality included are economic growth, energy consumption, FDI, trade openness and institutional quality. For empirical analysis, panel data is used for the period 1984 to 2015. The estimated results indicate that Environmental Kuznet Curve (EKC) hypothesis holds in South Asia, i.e., environment first deteriorates with economic development and then it starts improving. Empirical results reveal that 1% increase in economic growth worsens environment by 1.709%. However, further increase in economic growth improves environment by 0.104%. Energy consumption has deteriorating effect on environment. Financial development has degraded the environment in the region, which indicates that South Asian countries have used financial development for capitalization and not to improve technology. The estimated results show that 1% increase in financial development deteriorates environment by 0.147%. FDI, which is a measure of financial openness, has mitigating effect on pollution. In turn, trade openness has worsened the environmental quality in the region. Institutional quality has significant negative effect on carbon emissions. It also has significant negative moderating effects on carbon emissions. The findings show that 1% improvement in institutional quality will decrease pollution by 0.114%. The study suggests that South Asian countries should focus more on technology effect and not on scale effect of financial development.

The microalgae-based water treatment is gaining importance in recent years as it serves multiple purposes of which includes water treatment and biofuel production. Garcinia cambogia, a Malabar tamarind is a tropical fruit and the active ingredient hydroxycitric acid is popularly used as a weight-loss supplement. After extraction of the hydroxycitric acid, the wash water of G. cambogia is considered as an effluent. The potential microalgal species that can grow and treat G. cambogia wash water were isolated and identified as Dicloster acuatus BVR1 and Kalenjenia gelanitosa BVR2. Both the microalgal species adapted to G. cambogia wash water and entered exponential phase after sixth day with maximum specific growth rate of 0.310 day⁻¹ for D. acuatus and 0.296 day⁻¹ for K. gelanitosa during tenth day. The biomass productivity of D. acuatus was 0.03 g L⁻¹ day⁻¹ which is 58% higher than K. gelanitosa with 0.019 g L⁻¹ day⁻¹. The microalgal strains besides water treatment were subsequently subjected for lipid extraction and lipid productivity determination. The lipid productivity of D. acuatus was 2.68 mg L⁻¹ day⁻¹ which is lesser compared to 3.38 mg L⁻¹ day⁻¹ for K. gelatinosa. Both the microalgal isolates were promising for G. cambogia wash water treatment and lipid production. Hence, an environment friendly approach of water treatment with simultaneous lipid production for biofuel conversion is conducted.

Global consumption of synthetic dyes is roughly 7 × 10⁵ tons per year, of which the textile industry expends about two-thirds. Consumption of synthetic dyes produces large volumes of wastewater discharged into aquatic ecosystems. Colored effluents produce toxic effects in the hydrobionts, reduce light penetration, and alter the photosynthetic activity, causing oxygen depletion, among other effects. Some dyes, such as Congo red (CR), are elaborated with benzidine, a known carcinogenic compound. Information regarding dye toxicity in aquatic ecosystems is scarce; therefore, our study was aimed at evaluating the toxicity of CR on a battery of bioassays: the microalga Pseudokirchneriella subcapitata, the cladocerans Daphnia magna and Ceriodaphnia rigaudi, and the zebrafish Danio rerio. P. subcapitata was the most sensitive species to CR (IC₅₀, 3.11 mg L⁻¹); in exposed individuals, population growth was inhibited, but photosynthetic pigments and macromolecule concentrations were stimulated. D. magna was tolerant to high dye concentrations, the determined LC₅₀ (322.9 mg L⁻¹) is not an environmentally relevant value, but for C. rigaudi, LC₅₀ was significantly lower (62.92 mg L⁻¹). In zebrafish embryos, exposure to CR produced yolk sac edema, skeletal deformities, and stopped larvae hatching; lack of heart beating was the only observed lethal effect. CR affected organisms of different trophic levels diversely. Particularly, the effects observed in microalgae confirm the vulnerability of primary producers to dye-polluted wastewaters, because dyes produced toxic effects and interfered with photosynthesis. Different cladoceran species displayed different acute effects; thus, species sensitivity must also be considered when toxicity of dyes is assessed. Inhibition of fish larvae hatching is a significant effect not previously reported that warns about the toxicity of dyes in fish population dynamics. Synthetic azo colorants should be considered as emerging pollutants because they are discharged into the aquatic environment and are not currently included in the environmental regulation of several countries.