Low Levels Of Metals Research Articles

Exposure to metals and the disruption of sex hormones in 6–19 years old children: An exploration of mixture effects

BackgroundIndividual metals have been linked to sex hormones disruption, but the associations of metals mixture are rarely examined among children. MethodsA total of 1060 participants of 6–19-year-old who participated in the National Health and Nutrition Examination Survey (2013–2016) were included. Eighteen metals were quantified in the whole blood and urine. Sex hormones were measured in serum, including total testosterone (TT), estradiol (E2), and sex hormone binding globulin (SHBG). In addition, free androgen index (FAI) and the ratio of TT to E2 were calculated. Bayesian kernel machine regression and latent class analysis were performed to assess the associations of metals mixture and exposure patterns of metals at varied levels with sex hormones while adjusting for selected covariates. All analyses were conducted by sex-age and sex-puberty groups to explore the potential sex-dimorphic effects. ResultsExposure to metals mixture was associated with elevated levels of FAI and E2 among 12–19 years old girls. Moreover, the exposure pattern of metals that was characterized by high levels of blood and urinary cadmium, blood manganese, and urinary cobalt was associated with elevated E2 and reduced TT/E2 levels among girls of 12–19 years old. However, the associations of metals mixture with sex hormones were overall nonsignificant among boys. Nevertheless, metals exposure pattern that was characterized by high levels of blood lead, urinary barium, strontium, and lead but comparatively low levels of the other metals was consistently associated with reduced levels of FAI and E2 but elevated levels of TT/E2 and SHBG among boys of 12–19 years old. ConclusionMetals mixture and exposure patterns that were dominated by high levels of certain metals were associated with sex hormones imbalance among 12–19 years old children in a sex-dimorphic pattern, with the identified individual metals that drove the associations of metals mixture varied by sex.

Early pregnancy essential and non-essential metal mixtures and maternal antepartum and postpartum depressive symptoms

BackgroundMood disorders are common during and after pregnancy, and environmental metals may contribute to increased risk. Antepartum metal exposures have not been well characterized in relation to maternal depression. We evaluated the extent to which early pregnancy erythrocyte concentrations of essential and non-essential metals were prospectively associated with antepartum and postpartum depressive symptoms. MethodsParticipants were 1226 women in Project Viva, a longitudinal cohort recruited during pregnancy (1999–2002). We measured concentrations of 11 metals in maternal first trimester erythrocytes (arsenic, barium, cadmium, cesium, copper, mercury, magnesium, manganese, lead, selenium, zinc). Using the Edinburgh Postnatal Depression Scale (EPDS), we assessed elevated depressive symptoms (≥13; 0–30 scale) at mid-pregnancy and at 6 and 12 months postpartum. We applied latent class mixed modeling to identify symptom trajectories. Adjusting for maternal sociodemographics and co-exposures, we examined associations between the metal mixture and depressive symptoms using logistic (for EPDS≥13)/multinomial (for symptom trajectories) regression and quantile g-computation. ResultsIn this cohort of moderately high socioeconomic status participants (e.g., 72 % college graduate), low-level metal concentrations were weakly to moderately correlated (Spearman: ˗0.24 to 0.59); the prevalence of depressive symptoms ranged from 9 % (mid-pregnancy) to 6 % (12 months postpartum); and three trajectories (stable low; elevated mid-pregnancy, then decreasing; moderate mid-pregnancy, then increasing) best fit the EPDS data. The early pregnancy erythrocyte metal mixture was not associated with maternal depressive symptoms in logistic, multinomial, or mixture models. For individual metals, most confidence intervals (CI) included the null. There was weak evidence that arsenic, lead, and selenium were moderately associated with elevated odds of depressive symptoms and/or trajectories. However, the odds ratios (95 % CI) per doubling of these three metals were imprecise [e.g., arsenic: 1.13 (0.94, 1.40) for EPDS≥13 at six months postpartum; lead: 1.19 (0.80, 1.77) for EPDS≥13 at mid-pregnancy; selenium: 2.35 (0.84, 6.57) for elevated mid-pregnancy, then decreasing versus stable low trajectory]. DiscussionWe did not observe strong, consistent evidence of associations between early pregnancy erythrocyte metal concentrations and subsequent maternal antepartum and postpartum depressive symptoms.

Health risk indices associated with heavy metals from vegetables cultivated in Tsagero District, Rimi Local Government Area, Katsina State, Nigeria

Local preservation of vegetables involves drying to enhance shelf life. The drying processes could, in turn, contaminate the vegetables with environmental heavy metals. Ingestion of foods contaminated with heavy metals may lead to an increase in the chances of incurring cancer and other health disorders in the consumer population. This study investigated heavy metals contaminations and health risks associated with the consumption vegetables from Turaji, Tsagero District, Rimi Local Government Katsina State, North west Nigeria. The vegetables were three samples of Solanum lycopersicum L. (tomato) as fresh tomato, tomatoes sun-dried along tarred road side, and tomatoes air-dried on farmland soil; three samples of Capsicum annuum (sweet pepper) as fresh sweet pepper, sweet pepper sun-dried along tarred road side and sweet pepper air-dried on farmland soil. The samples were grinded, ashed and digested with HNO3 and HCl separately using standard methods. The heavy metals (Cu, Ni, Fe, Cr, Cd, Mn, Zn, and Pb) contents of the samples were analyzed using atomic absorption spectrophotometry. Daily intake, non-carcinogenic and carcinogenic risks as well as hazard indices of the heavy metals were determined. Results of the study showed that the vegetables analyzed generally have low levels of the heavy metals, with Ni being below detection level (BDL) in all the samples. All of the detected heavy metals concentrations were below the maximum permissible limits as set by the regulatory agencies. The calculated target hazard quotient (THQ) Health risk indices (HRIs) of the evaluated heavy metals in all the samples were therefore, less than 1. The Incremental Life time Cancer Risk (ILCR) to the population from consumption of the samples lies within the safe limit (≤10-4). From the results, these vegetables are hence, safe for human consumption.

3D-printed polymeric lattice-enhanced sustainable municipal solid waste incineration fly ash alkali-activated cementitious composites

The disposal of municipal solid waste incineration fly ash (MSWIFA) has become a prominent issue due to high environmental risks. In this study, as a potential aluminosilicate precursor, MSWIFA was further alkali-activated as a sustainable construction material in the form of an alkali-activated MSWIFA-based material (AAFM), with a low leaching level of heavy metals. Various 3D-printed polymeric lattices were designed and inserted into the AAFM to promote its inherent brittleness. A special coating was also considered to enhance the alkali resistance of the PEGT lattices. Through a flexural tension test with a 3D digital image correlation (3D-DIC) technique, the failure patterns and strain distributions of the 3D-printed polymeric lattice-enhanced MSWIFA-based composites were tracked. These polymeric lattice-containing composites indicated the promotion of mechanical performance, i.e., higher flexural strengths and good ductility. The 3D polymeric lattice-enhanced MSWIFA-based composites showed application prospects as sustainable construction materials, gaining both environmental benefits and good mechanical performance.

Metabolic and Oxidative Changes in the Fern Adiantum raddianum upon Foliar Application of Metals

Cadmium (Cd) or nickel (Ni) were applied as a foliar spray (1 µM solution over one month) to mimic air pollution and to monitor metabolic responses and oxidative stress in the pteridophyte species. Exogenous metals did not affect the metal content of the soil and had relatively little effect on the essential elements in leaves or rhizomes. The amounts of Cd and Ni were similar in treated leaves (7.2 µg Cd or 5.3 µg Ni/g DW in mature leaves compared with 0.4 µg Cd or 1.2 µg Ni/g DW in the respective control leaves), but Ni was more abundant in rhizomes (56.6 µg Ni or 3.4 µg Cd/g DW), resulting in a higher Cd translocation and bioaccumulation factor. The theoretical calculation revealed that ca. 4% of Cd and 5.5% of Ni from the applied solution per plant/pot was absorbed. Excess Cd induced stronger ROS production followed by changes in SOD and CAT activities, whereas nitric oxide (NO) stimulation was less intense, as detected by confocal microscopy. The hadrocentric vascular bundles in the petioles also showed higher ROS and NO signals under metal excess. This may be a sign of increased ROS formation, and high correlations were observed. Proteins and amino acids were stimulated by Cd or Ni application in individual organs, whereas phenols and flavonols were almost unaffected. The data suggest that even low levels of exogenous metals induce an oxidative imbalance, although no visible damage is observed, and that the responses of ferns to metals are similar to those of seed plants or algae.

Ecological risks of some heavy metals in sediment samples collected from downstream of the Red river

This study aimed to assess the accumulation of some heavy metals such as Cu, Pb, Cd, and Cr in the sediments collected from downstream of the Red river from the south of Hanoi city to Nam Truc district, Nam Dinh province. Besides, the geological accumulation index (Igeo) and the potential ecological risk index were calculated to understand the impact of heavy metal content in the sediments on the ecosystem. The results showed that the concentration of several metals (Cu, Pb, Cd, Cr) in 20 sediment samples was lower than the permitted values specified in Technical Regulations on sediment quality (QCVN 43:2017/BTNMT). However, according to the Canadian guidelines, the concentrations of metals in 50% of samples had a low level of effect. The potential ecological risk index of metals ranges from 1.8 to 11.6, revealing that the study area has a low-level metal risk. This data can clarify the area’s potential risk level and provide the scientific basis for recommending measures to control and reduce sources of metal pollution into the aquatic environment.

Physico-chemical factors influencing of selected paddy fields at Thiruvaiyaru Block Thanjavur District, Tamil Nadu, South India

This study focused on the Influencing physico-chemical parameters of the soil at different paddy sampling sites. The study period was January 2020 to June 2020. Soil samples were collected using the systematic-random sampling method and hand sorting method (25 x 25 x 30 cm). The study area of this research work is Thiruvaiyaru Block (Kandiyur, Karupur, Maharajapuram, Nadukauvery and Vilangudi) at Thanjavur District. Soil structure of the present study is Clay soil. The Total Nitrogen values ranged from 1.06±0.43 to 5.00±2.04 mg/acre; Total Phosphorus values ranged from 0.44±0.18 to 4.80±1.96 mg/acre and Total Potassium values ranged from 1.40±0.57 to 3.26±1.33 mg/acre. Following heavy metals are analyzed by atomic spectrophotometer. They are zinc, chromium, arsenic, lead, mercury and cadmium. The low level of heavy metals appears at all study sites. The origin of the nutrients and their availability certainly affect the soil quality, while the presence of low levels of heavy metals in the soil samples contaminates the paddy soil, which is a global problem.

Characterization of Agro-Livestock Wastes for Composting in Rural Zones in Ecuador: The Case of the Parish of San Andrés

In Ecuador, the agriculture and livestock sectors are very important within the economy of rural areas. These activities generate a large amount of waste whose management is not optimized. Thus, the aim of this work was to characterize different agro-livestock wastes generated in a rural area, the parish of San Andrés (Chimborazo-Ecuador), in order to know their composition to design suitable composting processes for their treatment. To this end, different physicochemical and chemical parameters were determined in 24 crop residue samples and 18 manure samples, and two piles were elaborated with the same proportion of wastes (51% vegetable residue + 35% cow manure + 14% sawdust) and composted by turning or passive aeration. Throughout the composting process, the temperature and oxygen concentration were recorded and the evolution of different physicochemical, chemical, and biological parameters and the quality of the final composts were studied. The results indicated that the agro-livestock residues presented notable macro and micronutrient and organic matter contents and low levels of heavy metals, these properties being positive for their subsequent treatment in a co-composting experiment. This experiment demonstrated that the composting processes are a feasible strategy for the treatment of these residues and yield compost with an adequate agricultural quality (notable nitrogen content, low heavy metal and soluble mineral salt contents and 92–94% in germination index). Moreover, the passive aeration system can be recommended because this aeration method reduced composting times and the work associated with the process. However, more studies are required on this composting system and other agro-livestock wastes to establish a management protocol for all the waste generated, which will contribute to the sustainability of the agro-livestock sector in the area studied.

Potential benefits of joint hypothetical interventions on diet, lead, and cadmium on mortality in US adults

BackgroundPrevious studies reported associations between high blood lead levels (BLLs) and urinary cadmium (UCd) concentrations and all-cause and cause-specific mortality. It is hypothesized that these associations are mediated by inflammation; therefore, adherence to an anti-inflammatory diet may mitigate these effects. We sought to estimate the potential effects of joint hypothetical interventions on metals levels and adherence to an anti-inflammatory diet or fruits and vegetables (FV) intake on the expected mortality distributions.MethodsWe used data on 14,311 adults aged ≥ 20 years enrolled in the NHANES-III between 1988 and 1994 and followed up through Dec 31, 2015. We estimated daily FV servings and adherence to the dietary inflammatory index at baseline using 24-hour dietary recalls. Mortality was determined from the National Death Index records. We used the parametric g-formula with pooled logistic regression models to estimate the absolute risk of all-cause, cardiovascular, and cancer mortality under different hypothetical interventions compared to the natural course (no intervention).ResultsOverall, we observed a decreased mortality risk when intervening to lower metals levels or increasing adherence to an anti-inflammatory diet or the daily FV servings. The joint intervention to lower BLLs and UCd and increase the adherence to the anti-inflammatory diet had the strongest impact on cancer mortality risk (risk difference [RD] = -1.50% (-2.52% to -0.62%)) compared to the joint intervention only on metals levels RD= -0.97% (-1.89 to 0.70). The same pattern of associations was observed for the joint intervention to lower both metals and increased daily FV servings and cardiovascular diseases mortality risk.ConclusionHigher diet quality may constitute a complementary approach to the interventions to reduce exposures to cadmium and lead to further minimize their effects on mortality. A paradigm shift is required from a pollutant-focused only to a combination with a human-focused approach for primary prevention against these metals.

Assessment of heavy metals distribution and environmental risk parameters in bottom sediments of the Pechora River estuary (Arctic Ocean Basin)

The article is devoted to the study of the content of heavy metals in the bottom sediments of the estuary of the Pechora River, which is the largest river in the European Arctic of Russia. In addition to metals, the particle size distribution and physicochemical parameters of river sediments were analyzed, such as the content of carbonates, organics and ash components. Average concentrations of heavy metals in the sediments of the Pechora Delta sediment have been found to be significantly lower than terrestrial values. The assessment of pollution and toxicity of sediments in the Pechora delta, made using various parameters Igeo, Cf, Cd, EF and ERI, showed a low level of heavy metals in bottom sediments, coupled with a low level of environmental risk. Despite the fact that high concentrations of heavy metals of anthropogenic origin are continuously recorded in the water of the Pechora River, (almost throughout the entire length), there is no accumulation of pollutants in the sediments of the delta. Thus, the estuary of the Pechora River, unlike other large estuary systems, does not act as a filter or sediment trap, which contributes to the penetration of heavy metals deep into the Barents Sea and the widespread distribution of pollutants in the ecosystems of the Arctic.

Genome-Wide Association Mapping of Grain Metal Accumulation in Wheat

Increasing wheat grain yield while ignoring grain quality and metal accumulation can result in metal deficiencies, particularly in countries where bread wheat accounts for the majority of daily dietary regimes. When the accumulation level exceeds a certain threshold, it becomes toxic and causes various diseases. Biofortification is an effective method of ensuring nutritional security. We screened 200 spring wheat advanced lines from the wheat association mapping initiative for Mn, Fe, Cu, Zn, Ni, and Cd concentrations. Interestingly, high-yielding genotypes had high essential metals, such as Mn, Fe, Cu, and Zn, but low levels of toxic metals, such as Ni and Cd. Positive correlations were found between all metals except Ni and Cd, where no correlation was found. We identified 142 significant SNPs, 26 of which had possible pleiotropic effects on two or more metals. Several QTLs co-located with previously mapped QTL for the same or other metals, whereas others were new. Our findings contribute to wheat genetic biofortification through marker-assisted selection, ensuring nutritional security in the long run.

Biosólidos como fertilizante en el cultivo de tomate

The sludge produced in wastewater treatment plants constitutes a potential alternative to replace traditional fertilizers and reduce costs in agricultural activities. The objective of this work was to compare the fertilizing effect of the sludge produced in the wastewater treatment plant of Sotaquirá-Colombia, with the fertilizers traditionally used on the tomato crop (Solanum lycopersicum L). For this, the sludge was previously stabilized with two different treatments: dehydration and the addition of CaO. Subsequently, four treatments were applied to the tomato seedlings, 135 g.kg-1 of dehydrated biosolid, 135 g.kg-1 biosolid stabilized with CaO, 135 g.kg-1 of ABIMGRA®, 135 g.kg-1 of naturcomplet®-G, and greenhouse soil without biosolids. The height of the plant, the fresh and dry mass, foliar area, and fruits per plant, were measured at 0, 30, 60 and 90 days after sowing. In tomato fruits, the concentrations of heavy metals, coliforms, helminth eggs, somatic phages, and Salmonella sp., were determined. The dehydrated biosolids had a significant effect on the size, the fresh mass, foliar area, and the number of fruits per plant, compared to the alkaline biosolids. The dry mass of the plants (120 g. plant-1) was similar to traditional fertilizers and biosolids. Tomatoes produced with biosolids had low levels of heavy metals and an absence of pathogenic microorganisms. In conclusion, the biosolid obtained by dehydration in Sotaquirá can be used as a potential fertilizer in tomato cultivation.

The Occurrences of Heavy Metals in Water, Sediment and Wild Shrimps Caught from Barito Estuary, South Kalimantan, Indonesia

The research investigated the occurrences of heavy metal (Pb, Cu, and Cd) in waters, sediments, and wild shrimps collected from the Barito River estuary. Water and sediment samples were collected from 11 study sites by purposive sampling. At the same time, shrimps samples were captured around the sites. The study showed low levels of heavy metals in water samples; those were: Cd<0.0019 mg/L, Cu<0.001 mg/L, and Pb<0.0019 mg/L. Low levels of heavy metals were also detected in sediment samples, those were Cd <0.24 mg/kg, Cu <0.013-0.69 mg/kg, and Pb<0.024 mg/kg. Heavy metals contaminations were detected in Parapenaeopsis sculptilis, those were Cd = 2.802 mg/kg; Cu = 3.399 mg/kg, and Pb = 1.294 mg/kg. In Acetes japonicus, the heavy metals concentration were Cd = 2.127 mg./kg, Cu = 5.518 mg/ kg, and Pb = 2.723 mg/kg. In Penaeus merguiensi, the heavy metals concentrations were Cd = 8.598 mg/kg, Cu = 6.403 mg/kg, and Pb = 5.433 mg/kg. This study indicated the increases of heavy metals concentrations from water to sediment and finally into the shrimps. The presence of heavy metals in shrimps indicated the bioaccumulation of toxic metals, especially for Pb and Cd concentrations which exceeded the tolerable limit according to JECFA.

Distribution and Influencing Factors of Metals in Surface Soil from the Yellow River Delta, China

To study metal enrichment and identify the influencing factors, 106 surface soils were collected in the Yellow River delta, including ten vegetation types. Concentrations of 10 different metals, including As, Cd, Cr, Ni, Cu, Pb, Zn, Mn, Al, Fe, and physicochemical properties pH, salinity, particle size were detected. The pH value was 7.35~9.17, and the salinity was in the range of 0.01~2.00%. The average value of silt was 76.18%, which was the main particle size for 99% of the samples. The mean concentrations of As, Cd, Cr, and Ni were higher than the background value of Shandong Province or the background value of yellow soil in China. A higher concentration of Fe occurred in Phragmites australis (mean concentration 2.50%) and paddy field. The concentrations of Cd, Cr, Ni, Cu, Pb and Zn were lower in the Suaeda salsa soil. The Nemerow pollution index indicated that 79% of all samples showed low-level metal pollution, and 7% of all samples showed moderate-level metal pollution. In the areas with higher salinity, the concentrations of As were higher, while the concentrations of Cd and Ni were lower. The correlation analysis showed that with increasing pH, the concentrations of As and Zn decreased significantly. The metal concentrations had a significant positive correlation with clay, except for As.

Mixture analysis of associations between exposure to low levels of multiple metals and semen quality and sperm DNA integrity

The objective of this study was to assess the association of exposure to metal mixtures with semen quality and sperm DNA integrity of coke oven workers (n = 96). Urinary six metals (cadmium, lead, arsenic, zinc, selenium, and copper) were quantified using inductively coupled-mass spectrometry. Semen quality parameters included sperm concentration, sperm concentration, sperm motility, sperm morphology, and sperm viability. Sperm DNA fragmentation and 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodGuo) adducts served as biomarkers for assessing sperm DNA integrity. Bayesian kernel machine regression with the hierarchical variable selection process was used for analyzing both individual and joint effects of the metal mixture on the outcomes of semen samples, while adjusting for age, smoking, alcohol consumption, job length, and body mass index. The metal mixture was associated with reduced sperm concentration, motility, viability, and normal morphology. It was novel that a dose-response relationship was observed between exposure of the metal mixture and semen quality. Among the metals tested, cadmium had a reverse relationship with sperm motility, viability, and normal morphology, and a non-linear relationship with sperm viability and sperm motility. The metal mixture and individual metals were not associated with sperm DNA fragmentation and 8-oxodGuo. In conclusion, exposure to metal mixtures and cadmium may exert an association with semen quality and had no association with sperm DNA breakages.

Vermistabilization of fecal sludge with organic enriched substrates for compost production using two earthworm species (Eisenia foetida and Eudrilus eugeniae)

AbstractDeveloping countries are facing high generation of fecal sludge without adequate systems for proper treatment, leading to detrimental effects on the environment from its disposal. An emerging and innovative option in curbing this problem is the use of epigeic earthworm species to stabilize the waste into vermicompost, a value‐added resource. Substrate enrichment techniques can be applied to promote the sustainability and effectiveness of the vermicomposting process. This study was therefore carried out to determine the potential of two epigeic earthworm species (Eisenia foetida and Eudrilus eugeniae) to transform and stabilize fecal sludge into vermicompost using organic enriched substrates. Enriched substrates were prepared with 160 g of coconut coir, 120 g of fecal matter (65–70% dry matter) and 80 g of organic black soil. Three treatments of the vermibed substrates were prepared which were labelled T1, T2 and T3, with T1 containing Eisenia foetida, T2 containing Eudrilus eugeniae and T3, the control treatment, containing no earthworm. Treatments were triplicated and about 3‐week‐old 20 clitellated, E. fetida (live weight ∼255–275 mg) were introduced into the vermibeds for vermicomposting over a duration of 12 weeks. Physicochemical parameters such as pH, organic carbon (Corg), total nitrogen (Ntot), available phosphorus (Pavail), exchangeable calcium (Caexch), iron (Fe), lead (Pb), and aluminium (Al) changes in the setups at the beginning and end of the vermicomposting period were evaluated. Eisenia foetida demonstrated a higher Corg mineralization (67.59%) compared to Eudrilus eugeniae, which attained 67.22%. Eisenia foetida also showed 5% more mortality than Eudrilus eugeniae. The study revealed that the two epigeic earthworm species for the vermicomposting of fecal waste in the enriched substrates played significant role in stabilizing the waste into vermicompost that was rich in nutrients, with lower levels of metals, higher levels of microbial biomass and higher levels of enzyme concentration.

Pilot Study to Quantify Palladium Impurities in Lead-like Compounds Following Commonly Used Purification Techniques.

Palladium-catalyzed reactions are among the most commonly used procedures in organic synthesis. The products have a range of uses, including as intermediates in total synthesis and as screening compounds for drug discovery or agrochemical projects. Despite the known and potentially deleterious effects of low-level metal impurities in biological assays, the quantification of metal remaining in reaction products to verify the effective removal of the transition element is rarely reported. Using palladium as an exemplar, we describe a pilot study that for the first time quantifies residual metal levels in reaction products following increasingly rigorous purification protocols. Our results demonstrate that significant levels of residual palladium can remain in isolated reaction products following chromatographic purification, and only by using a subsequent metal scavenging step are they reliably reduced to a low level. Finally, we provide a set of simple guidelines that should minimize the potential for issues associated with residual palladium in reaction products.

Metals and oxidative stress in aquatic decapod crustaceans: A review with special reference to shrimp and crabs.

The objective of this review is to synthetize knowledge of the relationship between metals and oxidative stress in aquatic crustaceans (mainly shrimp and crabs) to analyze antioxidant responses when organisms are exposed to metals because the direct metal binding to the active site of enzymes inactivates most of the antioxidant systems. This study reviewed over 150 works, which evidenced that: (i) antioxidant defense strategies used by aquatic decapod crustaceans vary among species; (ii) antioxidant enzymes could be induced or inhibited by metals depending on species, concentration, and exposure time; and (iii) some antioxidant enzymes, as superoxide dismutase increase their activity in low metal levels and time exposures, but their activities are inhibited with higher metal concentrations and exposure time.

Index of environmental pollution and adaptation of Avicennia marina around the ex-bauxite mining area in Bintan Island

Bintan Island has high bauxite resource potential. However, its utilization is not balanced with efforts to restore ex-mining land. Physical damage includes erosion and sedimentation of red mud along the coast and the surrounding mangrove forest. This study aims to determine environmental pollution based on the accumulation of lead (Pb) and chromium (Cr) in redmud found in mangrove forests around the bauxite ex-mining area and the adaptation of Avicennia marina to heavy metals. This research was conducted from April to December 2020. Research survey and laboratory analysis using Atomic Absorban Spectrophotometry. The results showed that Pb in the sediments and organs of A. marina was higher than Cr. The results showed that the mangrove forest around the bauxite ex-mining area of Bintan Island was contaminated with low levels of Pb and Cr metals (CF<1, PLI<1) and the environment is lightly polluted (0<Igeo<1). Adaptation of A. marina showed that the metal uptake mechanism was rhizofiltration (BCF<1, TF<1, BCF<TF) and the physical condition was slightly damaged. There was no significant effect between Pb and Cr metals in the sediments and organs of A. marina on the stem diameter and tree height (Sig.> 0.05).

Stabilization of Spent Grains by Composting: Case of the BB Brewery in Lom&amp;#233; (Togo)

Brewery grains have a long history in animal feed. This use in animal feed nevertheless poses a problem, that of bad odors due to the sometimes too long shelf life of spent grains. The objective of this work is to recover spent grains from the BB brewery in Lomé by composting in order to stabilize them. A compost based solely on spent grains was produced after 5 months. The physico-chemical and spectroscopic characterizations at the end of the composting process revealed that the compost obtained has interesting properties with a pH = 7.01; a C/N ratio of 13.7 and a low level of heavy metals (Pb = 1.23 mg/kg, Cd = 0.04 mg/kg etc.).