Identification Of Contaminants Research Articles

Identification and Characterization of Mercury Contamination in Vegetables and Herbs Cultivated on a Commercial Vertical Indoor Farming System with Light-Emitting Diode Lighting: Unveiling an Unusual Food Safety Risk of Some Improperly Manufactured High-Density Agricultural Production Systems.

Artificial grow lights, such as light-emitting diodes (LEDs) and fluorescent grow lights, are commonly used in modern day indoor farming, citing advantages in energy efficiency and a higher controlled environment. However, the use of LEDs poses a risk in mercury contaminations as a result of its production process, specifically LEDs with polyurethane encapsulates that were traditionally produced using mercury resins as a catalyst. A total of 10.0 ppm of mercury was detected in a curly kale sample harvested from an indoor hydroponic vegetable farm, exceeding Singapore Food Regulation's limit of 0.05 ppm. Vegetables, farming inputs, and surface swabs from the affected farm were analyzed using wet acid digestion followed by cold vapor atomic absorption spectroscopy analysis. The investigation found high concentrations of mercury in the LED encapsulant, and the encapsulant material was identified to be polyurethane by Fourier transform infrared spectroscopy and pyrolysis-gas chromatography-mass spectrometry analysis, indicating the source of mercury contamination to be the LED polyurethane encapsulant.

Deep mining of reported emerging contaminants in China's surface water in the past decade: Exposure, ecological effects and risk assessment.

The identification and management of high-risk contaminants have raised great concern from governments. Facing the growing amount of data on the occurrence of emerging contaminants (ECs) in surface water, a deep mining and quality control strategy was developed to integrate data on all reported ECs in Chinese surface water over the past decade, and an exposure and effect database was further built. In addition, multilevel risk characterization was carried out to prioritize high-risk areas, contaminants and endpoints. A total of 1038 ECs, mainly pharmaceutical and personal care products (PPCPs) and industrial chemicals, were curated, with concentrations ranging from 0.02 pg/L to 533µg/L. For individual risk, all the provinces had acceptable risks except for Henan, which was characterized with a medium chronic risk. Nine ECs, including 4-nonylphenol and estrone, dominated individual risks. Conversely, for multisubstance risk, 76.20% and 73.87% of aquatic organisms were affected acutely and chronically at the national level, with acute and chronic risks exceeding the safety threshold of 5% in 11 and 19 provinces, respectively. Nineteen ECs, including sitosterol and chyfluthrin, dominated the multisubstance risk. In addition, 9 MoAs mainly inducing electron transfer inhibition, neurotoxicity and narcosis toxicity are high-risk endpoints. The study revealed the ecological risk status and key risk entities of Chinese surface waters, which provided the latest data to support the control of ECs in China.

The Ability of Near-Infrared Spectroscopy to Discriminate Plant Protein Mixtures: A Preliminary Study

The aim of this paper was to evaluate the effect of two different matrices (e.g., starch base flour vs. protein base flour) on the ability of near-infrared (NIR) spectroscopy to classify binary mixtures of chickpea (protein), corn and tapioca (starch) flours. Binary mixtures were made by mixing different proportions of chickpea plus corn, chickpea plus tapioca, and corn plus tapioca flour. Spectra were collected using NIR spectroscopy and the data analyzed using techniques such as principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). The results showed an effect of the matrix on the PLS-DA classification results, in both classification rates and PLS loadings. The different combinations of flours/mixtures showed changes in absorbance values around 4752 cm−1 that are associated with starch and protein. Nevertheless, the use of NIR spectroscopic might provide a valuable initial screening and identification of the potential contamination of flours along the supply and value chains, enabling more costly methods to be used more productively on suspect samples.

Meta-analysis of microbial source tracking for the identification of fecal contamination in aquatic environments based on data-mining

Microbial source tracking (MST) technology represents an innovative approach employed to trace fecal contamination in environmental water systems. The performance of primers may be affected by amplification techniques, target primer categories, and regional differences. To investigate the influence of these factors on primer recognition performance, a meta-analysis was conducted on the application of MST in water environments using three databases: Web of Science, Scopus, and PubMed (n = 2291). After data screening, 46 studies were included in the final analysis. The investigation encompassed Polymerase Chain Reaction (PCR)/quantitative PCR (qPCR) methodologies, dye-based (SYBR)/probe-based (TaqMan) techniques, and geographical differences of a human host-specific (HF183) primer and other 21 additional primers. The results indicated that the primers analyzed were capable of differentiating host specificity to a certain degree. Nonetheless, by comparing sensitivity and specificity outcomes, it was observed that virus-based primers exhibited superior specificity and recognition capacity, as well as a stronger correlation with human pathogenicity in water environments compared to bacteria-based primers. This finding highlights an important direction for future advancements. Moreover, within the same category, qPCR did not demonstrate significant benefits over conventional PCR amplification methods. In comparing dye-based and probe-based techniques, it was revealed that the probe-based method's advantage lay primarily in specificity, which may be associated with the increased propensity of dye-based methods to produce false positives. Furthermore, the heterogeneity of the HF183 primer was not detected in China, Canada, and Singapore respectively, indicating a low likelihood of regional differences. The variation among the 21 other primers may be attributable to regional differences, sample sources, detection techniques, or alternative factors. Finally, we identified that economic factors, climatic conditions, and geographical distribution significantly influence primer performance.

Advances of hyphenated technique in impurity profiling of active pharmaceutical ingredients and pharmaceutical products

AbstractImpurities found in active pharmaceutical ingredients (APIs) and pharmaceutical products are of ever‐increasing interest. According to several regulatory agencies, purity and impurity profiles are essential. An impurity is defined as any additional inorganic or organic material, residual solvents other than the medicinal components, or undesired compounds that remain with APIs. Impurities and degradation products in bulk drug materials and pharmaceutical formulations are identified, their structures are clarified, and their quantitative determination is part of impurity profiling. Unrecognized, poisonous impurities are dangerous to health and should be identified by selective procedures to increase the safety of drug therapy, and impurity profiling has become more significant in pharmaceutical analysis. This review briefly introduces process and product‐related impurities and emphasizes the creation of cutting‐edge analytical techniques for identifying them. It discusses the use of analytical methods, particularly high‐performance thin‐layer chromatography, liquid chromatography with mass spectrometry (MS), ultrahigh‐performance liquid chromatography, gas chromatography–MS, and nuclear magnetic resonance spectroscopy for the identification of contaminants and degradation products. It has discussed the importance of the quality, efficacy, and safety of drug substances and products, including the origin, types, and quality control of impurities, the need for the development of impurity profiling methods, impurity identification, and regulatory aspects.

Effect of Soil Contamination on Human Health and Environment with Preventive Measures: A Review

This study reviews the identification and effect of soil contamination to human health and environment. Soil contamination give direct and indirect impact to human health and environment. Various methods have been introduced and briefly elaborated in this review study in order to identify and monitor soil quality. The contamination status of soil is determined by several approaches and analysis of heavy metal in soil. The land uses of industry and landfill were found to have higher hazard for human and environment, when compared to the mining, plantation, and residential areas. As a preventive measure to the soil contamination, most country worldwide has developed and enforced Soil Quality Standard and Guidelines. With the enforcement of the standard and guidelines, the soil and land can be well managed and controlled from contamination by irresponsible person. This study is important for the environmental management of potentially toxic metals especially in the land uses of industry and landfill.

Microplastic Contamination in Waters and Sediments in the Selorejo Reservoir, Malang Regency, East Java

Microplastics are small plastic particles under 5 mm in size that have contaminated a lot of ecosystems, both aquatic and on land. The existence of heaps of garbage and the existence of fishing activities around residential areas are some examples of anthropogenic activities that are on the edge and water bodies of the Selorejo Reservoir. This study aims to observe the contamination of various types of microplastics and their abundance in water and sediment samples taken from the Selorejo Reservoir. Sampling was carried out using the selected method (purposive sampling) at five different stations, including the Konto River inlet, Kwayangan River inlet, settlements (blendrang), tourism areas, and reservoir outlets. Each station has 3 transects (as replicates) and about 100 liters of water and 1000 grams of sediment are taken. Destruction of water and sediments uses 30% H2O2 and 30% H2SO4 acid to remove organic components that are still attached and to facilitate observation under a stereo microscope with 400X magnification. Based on the results of an analysis of the abundance of microplastics in the waters of each station, the highest abundance of microplastics was successively found in the Konto river inlet with a total abundance value of 39.27x101 particles/liter, then in the residential part (blendrang) a number of 35.34x101 particles/liter, tourist areas 33.67x101 particles/liter, outlet 30.36x101 particles/liter and Kwayangan river inlet 29.67x101 particles/liter. Meanwhile, the highest total abundance of microplastics found in sediments in the Selorejo Reservoir was found successively in the Konto river inlet with a total abundance value of 3.68 particles/gram, then in the tourist area 2.08 particles/gram, in the Kwayangan river inlet 1.56 particles/gram, in the residential part (blendrang) a number of 1.2 particles/gram and outlets 1.12 particles/gram. Each type of microplastic is then counted based on the amount found. The results of the identification of microplastic contamination in waters and sediments in the Selorejo Reservoir found several types of microplastics, namely fibers, fragments, filaments, and films. The dominating type and color of microplastic is black fiber.

Contamination Level Prediction: Progress in Species Separation by TGA/MS

Molecular contamination can be detrimental to spacecraft life expectancy as it may induce changes to the properties of the surfaces on which it deposits. In order to control these potential issues, manufacturers need to assess in-flight contamination levels in the quite early design phases, possibly leading to design changes or extra material bake-out to fulfil requirements. The accuracy of model assessments may thus have direct impacts on missions and costs. Prediction of outgassing and deposition at mission timescale is done by extrapolating short-term on-ground experimental results, by fitting the latter with some empirical or physical laws. Common methods are the power law interpolation (in isothermal conditions) or the residence time approach (with thermally activated time constants), which leads to exponential decays in isothermal conditions. Although they allow fitting the measured outgassed flux over few-day-long experiments, their extrapolation to ten or fifteen-year-long missions is more challenging. Validating empirical laws might involve long-term empirical comparisons, while obviously the validation of physical models should start with checking their physics. In spite of many years trying, a basic difficulty was yet found to block significant progress on physical validation. As long as measurements are limited to the total mass on QCMs it looks possible to fit data as a sum of almost any law, such as residence time or diffusion models e.g. for outgassing. Following this observation, a conclusion was drawn that the only way to discriminate between two different physics was to characterize contamination at chemical species level. Such characterizations are a prerequisite to unravel the physics at play during several phenomena: outgassing, deposit films dynamics, photochemistry, environment/ATOX interactions, etc. This innovative approach, presented herein, aims at identifying outgassed contaminants by means of coupled thermogravimetric analysis and mass spectrometry. For this purpose, this paper reports the successful species separation and identification of contaminants outgassed from a material used in space applications: the epoxy adhesive Scotchweld EC-9323-2.

Fourier Transform Mid-Infrared Spectroscopy (FT-MIR) as a Method of Identifying Contaminants in Sugar Beet Production Process-Case Studies.

Food safety has received considerable attention in recent years. Methods for rapid identification of a variety contaminants in both the final product and the manufacturing process are constantly developing. This study used Fourier Transform Mid-Infrared Spectroscopy (FT-MIR) spectroscopy to identify various contaminants endangering white sugar production. It was demonstrated that inorganic compounds (calcium carbonate-CaCO3), plastic contaminants (polypropylene), and oily contaminants (compressor sealing and lubrication lubricant) can be identified with a high degree of precision. FT-MIR spectroscopy was proved to be a useful technique for detecting sugar contaminants rapidly and precisely even without the application of a sophisticated spectra analysis. Commercial databases of reference spectra usage significantly simplify and facilitate the application of this method.

Sources and Prevalence of Aflatoxin B1 in Different Rice Paddies of Punjab and Sindh, Pakistan

Rice is a major cash crop used all over world. The hygroscopic nature of rice kernel with warm and fumic conditions is favorable to enhance the growth and development of toxigenic fungi which produce mycotoxins. This study estimates the prevalence of aflatoxin B1 in different rice paddies collected from twelve regions of the Punjab and Sindh provinces of Pakistan. All the samples were analyzed for their phenotypic characteristics (appearance, odor, and grain length). Competitive Enzyme Linked Immuno Sorbent Assay (ELISA) was used to evaluate AFB1, both before and after applying the steam decontamination procedure to detoxify aflatoxin contamination. Cultural assay was used to find the source of aflatoxin. PDA and SDA agar were used to detect aflatoxin producing fungal species. Lactophenol Cotton Blue (LCB) staining was used for microscopic identification of fungal contaminants. Paddies from most regions appeared yellowish in color and odorless with the exception of Hafizabad, Jhang, Sheikhupura, and Gujarat (in Punjab), where they appeared blackish yellow in color and with a pungent smell. According to the results, 43 (61.42%) samples were detected with aflatoxin B1 out of 70 samples, with an average of 15.86±1.7 ug/kg, before treating with seam. After treatment with steam, 7 (10%) samples were detected with aflatoxin B1, with an average of 2.55±1.51 ug/kg. Most regions showed the presence of P. chrysogenum with the exception of R.Y. Khan, which showed the presence of A. niger. Steam, on average, reduced aflatoxin to 51.42%. The current study indicates that steam is an effective treatment to eradicate aflatoxin at industrial level. New approaches may be explored to target the contaminants in order to ensure food safety.

Fast recognition model of Fusarium in agaric based on hyperspectral imaging

AbstractAgaric is a dual‐purpose fungus for medicine and food, which is considered a healthcare product. However, in cultivation and production, agaric is contaminated by a variety of molds, resulting in a decline in quality and yield. Fusarium, as one of the poisonous filamentous fungi, seriously threatens the healthy development of the agaric industry and even affects human health. Therefore, it is necessary to establish timely and accurate identification and rapid detection of pathogens and crops. In this study, the visible near infrared hyperspectral imaging was used to obtain the image and spectral information, and the best classification model was selected and established to quickly distinguish Fusarium oxysporum from Fusarium verticillioides, which was also successfully applied for the preliminary identification of agaric infection. This approach could provide a nondestructive manner for rapid identification and detection of pathogenic fungi contamination in agaric.

A "peptide-target-aptamer" electrochemical biosensor for norovirus detection using a black phosphorous nanosheet@Ti3C2-Mxene nanohybrid and magnetic covalent organic framework.

Norovirus (NoV) is a major foodborne pathogen responsible for acute gastroenteritis epidemics, and establishing a robust detection method for the timely identification and monitoring of NoV contamination is of great significance. In this study, a peptide-target-aptamer sandwich electrochemical biosensor for NoV was fabricated using Au@BP@Ti3C2-MXene and magnetic Au@ZnFe2O4@COF nanocomposites. The response currents of the electrochemical biosensor were proportional to the NoV concentrations ranging from 0.01-105 copies/mL with a detection limit (LOD) of 0.003 copies/mL (S/N=3). To our best knowledge, this LOD was the lowest among published assays to date, due to the specific recognition of the affinity peptide and aptamer for NoV and the outstanding catalytic activity of nanomaterials. Furthermore, the biosensor showed excellent selectivity, anti-interference performance, and satisfactory stability. The NoV concentrations in simulative food matrixes were successfully detected using the constructed biosensor. Meanwhile, NoV in stool samples was also successfully quantified without complex pretreatment. The designed biosensor had the potential to detect NoV (even at a low level) in foods, clinical samples, and environmental samples, providing a new method for NoV detection in food safety and diagnosing foodborne pathogens.

A systematic review on recent trends and perspectives of biosensors in food industries

AbstractThe food industry has inappropriate techniques for process and quality control and requires techniques that can provide information on the physical and chemical properties of food quickly and affordably. Food applications mostly focus on the identification of contaminants, with a few significant analytes, such as sugars, alcohols, amino acids, flavors, and sweeteners, as exceptions. Biosensors can bring about an analytical revolution to address the problems facing the food and agriculture industries. Potential applications for biosensors include contaminant detection, product freshness monitoring, content verification, and raw material conversion monitoring. These studies are costly and time‐consuming due to the extraction or pre‐treatment of samples. This review gives an overview of biosensors with their classification and application in different food industries such as the fruits and vegetable industry, dairy, and meat industries. The application of biosensors in detection, quality assurance, and food safety is discussed in detail with their potential application.

Implementation of Aseptic Dispensing for Non-Cytostatic Injectable Drugs in the Internal Medicine Inpatient Ward of 'X' Hospital, West Java

Aseptic Dispensing activity is a procedure to minimize pharmaceutical preparations from the threats of pyrogens and contaminants. This study aims to determine the implementation of aseptic dispensing for non-cytostatic injectable drugs and the sterility of intravenous mixed preparations in the Internal Medicine Inpatient Ward of 'X' hospital, West Java for the period January - February 2022. This was a descriptive observational prospective study with a cross sectional approach. Researchers made direct observations of dispensing personnel, room and equipment as well as the process of aseptic dispensing activities including the stages of preparation, mixing, storage and disposal as well as sterility test of aseptic dispensing products. Based on the study results, it was obtained that of the 150 intravenous mixed preparations collected, there were 40 activities of diluting intravenous preparations, 100 activities of packaging into ready-to-use preparations and 10 activities of mixing intravenous preparations into infusion fluids, room suitability by 74%, preparations arrangement procedure by 68%, mixing procedure by 44%, storage procedure by 100% and disposal procedure by 63%. It can be concluded that the aseptic dispensing of non-cytostatic injection drugs in the internal medicine inpatient ward of 'X' hospital, West Java was not in accordance with the guidelines, especially at the mixing procedure stage (≤50). Compliance of dispensing personnel and room cleanliness during the process of mixing intravenous preparations need to be considered. The result of the identification of contamination during the aseptic dispensing activity of non-cytostatic injectable drugs showed that 1 in 150 samples (0.66%) was contaminated.

MICon Contamination Detection Workflow for Next-Generation Sequencing Laboratories Using Microhaplotype Loci and Supervised Learning

Innovation in sequencing instrumentation is increasing the per-batch data volumes and decreasing the per-base costs. Multiplexed chemistry protocols after the addition of index tags have further contributed to efficient and cost-effective sequencer utilization. With these pooled processing strategies, however, comes an increased risk of sample contamination. Sample contamination poses a risk of missing critical variants in a patient sample or wrongly reporting variants derived from the contaminant, which are particularly relevant issues in oncology specimen testing in which low variant allele frequencies have clinical relevance. Small custom-targeted next-generation sequencing (NGS) panels yield limited variants and pose challenges in delineating true somatic variants versus contamination calls. A number of popular contamination identification tools have the ability to perform well in whole-genome/exome sequencing data; however, in smaller gene panels, there are fewer variant candidates for the tools to perform accurately. To prevent clinical reporting of potentially contaminated samples in small next-generation sequencing panels, we have developed MICon (Microhaplotype Contamination detection), a novel contamination detection model that uses microhaplotype site variant allele frequencies. In a heterogeneous hold-out test cohort of 210 samples, the model displayed state-of-the-art performance with an area under the receiver-operating characteristiccurve of 0.995.

Convenient cucurbit[8]uril-based supramolecular fluorescent probe for efficient detection of phenolic contaminants

The serious environmental pollution problem has been one of the topics of concern as people become more aware of environmental protection. Phenolic compounds, which are widely used in various industries, have become one of the important water pollutants, causing great harm to humans, animals and plants, and it is crucial to develop a convenient and rapid method for the detection of trace phenolic contaminants. Among the many methods for detecting phenolic pollutants, fluorescent probes stand out for their high sensitivity, rapidity and efficiency. In this paper, a water-soluble fluorescent guest molecule (DPA) was successfully synthesized and self-assembled with cucurbit[8]uril (Q[8]) by host-guest interaction for the detection of phenolic contaminants, which can effectively distinguish 20 common phenolic contaminants, and more interestingly, the addition of 2,4,6-trinitrophenol not only effectively quenched the fluorescence, but also formed a ternary complex to settle down from the aqueous solution. This effective supramolecular fluorescence probe provides a new method for the rapid identification of phenolic contaminants in water.

Investigation of sorption mechanisms of chemical contaminants in PHBV‐based food packaging material: Impact on closed‐loop mechanical recycling opportunities

AbstractThe identification of contaminants on postconsumer food packaging is crucial for developing/adapting decontamination technology of closed‐loop mechanical recycling. So far, almost all contamination studies were conducted on PET bottles, with results extrapolated to other polymers. This work investigates the sorption mechanisms of three contaminants (Benzophenone, Ferulic acid and Irganox 1076), with different molecular weights and polarity, on the biodegradable polymer PHBV. Characterization of their respective partition coefficient (KP/L) and diffusion coefficient (D), under realistic conditions of use (contact with food simulants), allowed the modeling of their concentration profile in the thickness of the material. The results show a sorption in the core of PHBV of these three molecules, reached after a few hours/days. On the contrary, the same model applied to PET reveal a very slow sorption (several years), and only at the surface of the material. This study highlights the impact of polymer structure (chain mobility, polarity…) on contaminant sorption. The behavior of each polymer towards contaminants is directly related to its structure under given conditions of use, and it is a mistake to continue to address the decontamination processes of all polymers, based on the nature and level of contamination of PET.

Analysis of changes on substrates filling constructed wetland systems after landfill leachate treatment - FTIR study

A rapid and inexpensive method, Fourier transform infrared spectroscopy (FTIR), can be used to identify impurities and determine the functional groups responsible for the sorption of specific ions. The FTIR method has already been used in research. However, there is a lack of research on constructed wetland (CW) infill materials used to treat landfill leachate (LL). Therefore, the aim of this study was to verify the changes occurring in selected substrates (zeolite, expanded clay and bark) constituting vertical flow CW infill (VFCW) supplied with municipal LL. The principal component analysis carried out mainly showed differences in the results between the variants of the experiment with an infill of expanded clay and the others (for the values obtained at wave numbers in the range 1600-400 cm−1, in which most changes occurred). All peaks of the FTIR spectra of the pine bark filling the CW differ in location and intensity between the samples. In most cases, the stripes were elongated at exposure to 25% and 100% LL (compared to tap water). In all CW variants infill made of zeolite, peaks occurred at wave numbers within 1049-1012 cm−1, which were most likely caused by the presence of inorganic substances corresponding to clay minerals, and to silica. The FTIR spectra for zeolites, do not show large differences between the different infill samples used for LL treatment (100% LL and 25% LL). In all CW variants with expanded clay infill, peaks in the 1250-900 cm−1 wave number region, possibly indicating the presence of polysaccharides and phosphodiesters. FTIR spectroscopy has proven to be a very useful tool for rapid grade assessment determination of changes occurring on selected substrates and the identification of contaminants that remained after treatment in VFCWs fed with LL.

Untargeted Screening and Identification of Contaminants Using Gas Chromatography Coupled to High-Resolution Accurate Mass–Mass Spectrometry: Novel Solutions for Applied Testing Laboratories

The combination of gas chromatography (GC) instruments with quadrupole-based mass spectrometers is a common analytical setup for the detection of a broad range of volatile and semivolatile contaminants. GC–mass spectrometry (MS) (nominal mass) instruments are well known for their robustness and ease of use. However, they have some important limitations. Single quadrupole instruments can perform full scan analysis, but their sensitivity and selectivity in this mode are limited. Triple quadrupole (GC–MS/MS) systems are limited to a targeted acquisition within a specified compound list. High-resolution accurate mass (HRAM) mass spectrometry can overcome these limitations.

Identification of metallothionein protein in Anodonta woodiana as a biomarker of mercury (Hg) contamination

Abstract. Rahayu SYS, Fadila A, Fahmi MR. 2023. Identification of metallothionein protein in Anodonta woodiana as a biomarker of mercury (Hg) contamination. Nusantara Bioscience 15: 90-94. Heavy metal contamination can affect the survival of aquatic biota and will accumulate in the bodiesorganisms. Moreover, contamination identification at the molecular level can be analyzed using biomarker analysis. Biomarkers are responses measured individually, ranging from enzymes and xenobiotic measurements to organ and overall conditions. Biomarker analysis can be done by checking the metallothionein protein, this expression can be induced by Reactive Oxygen Species (ROS). Metallothionein (MT) has a thiol group with nucleophilic properties. As a result, this group can make Metallothionein able to find metals and free radicals. Therefore, prevention that can be done to reduce contamination at a higher trophic level requires monitoring the molecular level by observing the metallothionein protein. For example, Anodonta woodiana (Rea, 1834) or kijing taiwan induced by HgCl2 aims to characterize their absorption ability in the environment through metallothionein protein. That was conducted by the SDS-PAGE (Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis) method. SDS-PAGE electrophoresis results showed that the size of the metallothionein protein was 7 kDa, 15 kDa, and >30 kDa. Size >30 kDa is a group of proteins related to stress control or Heat shock protein (Hsp). The presence of Hsp is due to the body increasing stress protein synthesis and metallothionein to reduce normal protein synthesis. Based on the results obtained, this study revealed that A. woodiana could absorb HgCl2, as evidenced by the metallothionein protein characterization results.