Commission Of European Communities Research Articles

Perbandingan Dosis Radiasi Pemeriksaan Radiografi Thoraks PA Menggunakan Faktor Eksposi: Standar dan High kVp Berdasarkan Database DRL Si-INTAN BAPETEN

The usage of high kV has yet to be debated, so it is not fully used in PA chest radiographic examinations. However, The World Health Organization (WHO) and the Commission of European Communities (CEC) recommend using high kV, which can reduce the radiation dose to a minimum while maintaining the quality of the radiographic image. This study aimed to analyze the radiation dose for posterior-anterior (PA) chest radiography examinations using exposure factors: standard and high kV. This research method uses a retrospective study of the results of PA chest radiography examinations database diagnostic reference level (DRL) BAPETEN between 2018-2022. The PA chest examination data are the procedure, patient position, age, body weight, exposure factors (kVp and mAs), and ESAK dose (mGy). Then, use a standard exposure factor between 60-75 kVp and tube current-time of 6-12 mAs, while the exposure factor is high kV between 90-109 kVp and tube current-time of 0.7-4 mAs. After that, statistical analysis was carried out using IBM SPSS version 26 and Microsoft Excel. Determination of the average value and percentage difference in radiation dose of standard exposure factors and high kV. Then, proceed with statistical tests mann-whitney to determine the difference in the average radiation dose value between standard and exposure factors high kVp. The study showed that the average radiation dose for the standard kV exposure factor for the PA chest radiography examination was 0.179 mGy, while the high kV was 0.146 mGy. The dose difference between standard kV and high kV is 18.43%, with exposure factor radiation dose high kV lower than the standard exposure factor. For statistical test results, mann-whitney results p-value < 0,000. High kV could be a procedure to optimize exposure factors for PA chest radiography examination. Keywords: Exposure factors, High kV, Optimization, DRL, Chest PA

Key Types of Crowdsourcing in Science: Systematic Literature Review

Recent changes in information systems technology, combined with the postulates of open access to information, are causing the processes of knowledge production and dissemination to change. The necessity of the democratization of science, scientific openness, social orientation of science and the involvement of stakeholders from outside the scientific community in conducting research becomes a necessity for researchers. This is also in line with the guidelines of the European Commission's Community Research and Development Information Service, according to which academics are expected to change the ways of creating knowledge, be oriented towards solving social problems or transgress traditional disciplinary boundaries. Crowdsourcing in science is a collaborative online process through which scientists involve a group of self-selected individuals of varying, diverse knowledge and skills, via an open call to the Internet and/or online platforms, to undertake a specified research task or set of tasks. While research efforts to date have focused on the benefits of crowdsourcing in science, its typology has yet to mature. Typologies are important in describing complex, multidisciplinary organizational forms such as crowdsourcing in science. The main purpose of this article is to identify and provide a typology of crowdsourcing in science. Based on the thematic analysis of publications collected in a systematic manner and focused group interviews, 12 types of crowdsourcing in science are identified. The proposed crowdsourcing in science typology matrix may be a starting point for future research and decision-making by practitioners regarding the choice of a specific type of crowdsourcing in science.

Determination of the Element Values of Rainbow Trout (Oncorhynchus mykiss Walbaum, 1792) Eggs

The objective of this study was to determine the amount of the elements of rainbow trout (Oncorhynchus mykiss Walbaum, 1792) eggs obtained from different stations. The study was conducted in 5 different production areas that are producing the most rainbow trout eggs in Turkey. Element analysis (Na, Mg, Al, P, K, Ca, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Cd, Ba, Pb, Hg, and Cu) of rainbow trout eggs were performed using ICP-MS (Inductively Coupled Plasma- Mass Spectrometer). At the end of the study, it was determined that the daily consumption limit for selected elements (Ca, P, Mg, Zn, Mn, Ni and Se) was not exceeded in individuals consuming 100g of rainbow trout eggs per day. The daily intake recommended by the European Communities Commission was determined to be sufficient for the K, Ca, P, Mg, Fe, Zn, Cu and Mn elements in rainbow trout eggs. The Cd and Pb values of rainbow trout eggs obtained from different stations were determined significantly less than the values included in the Turkish Food Codex. The results of this study were thought to be important for both consumers and juvenile rainbow trout producers.

Measuring Serum Toxicity Markers to Evaluate the Safety of Commercially Available Spirulina Products in Mice

Spirulina a multicellular, blue-green alga has drawn attention as a viable food supplement due to its suitable nutrient composition, however, there is a dearth of information regarding its safety. This study aimed to measure the heavy metal concentrations in commercially available Spirulina products and evaluate the safety using the in vivo method. A total of 54 mice were randomly divided into three groups; Group 1 (n = 18) served as a control and received a basal diet. Group 2 (n = 20) served as a test and received Spirulina powder (15%) blended with a basal diet. Group 3 (n = 16) serves as a standard and received a basal diet supplemented with nutritional supplements. The findings showed that the concentration of serum aspartate aminotransferase, alanine aminotransferase, cystatin C, and troponin I after consuming the experimental diets was not statistically different between groups (p > 0.05). The concentrations of mercury (0.000036 mg/kg), lead (0.0047 mg/kg), cadmium (0.00048 mg/kg), and arsenic (0.0046 mg/kg) was very little to cause toxic effect and the levels were below the European Communities Commission (EC) recommended maximum heavy metal levels in foodstuffs. Therefore, consumption of Spirulina at a proportion of 15% does not exert any hepatic, renal, and cardiac toxicities in the mice. However, evaluating the safety of higher doses (> 15%) is required.

Enabling appropriate use of antibiotics: review of European Union procedures of harmonising product information, 2007 to 2020.

IntroductionAntimicrobial resistance (AMR) is one of the most important challenges in modern clinical practice. The European regulatory network has a strategy to support prevention of AMR by applying specific referral procedures.AimThe aim of this study was to evaluate post-authorisation changes made in the product information of key antibiotics that underwent referral procedures between 2007 and 2020.MethodIn a comprehensive analysis of the changes made for antibiotics, we extracted information on changes from the European Commission community register of medicinal products and the European Medicines Agency’s database for antibiotics that went through referrals. Changes made in the specific sections of the summary of product characteristics of each referral procedure were scrutinised.ResultsWe identified 15 antibiotics from seven classes of antibiotics during the study period. The outcome of all referrals included the restriction of antibiotic use. Therapeutic indications were revised for all antibiotics, with septicaemia and gonorrhoea most common diseases removed. Posology and/or method of administration was updated for all; the majority of referrals included adjustment of dosage for specific populations. Information on contraindication (most regarding hypersensitivity) and information on warnings was amended for all referrals.ConclusionOur findings highlight the importance of the regulatory actions. The changes made in the product information aim to ensure appropriate use. Ongoing harmonisation activities are likely to lead to further refinements and restrictions on individual antibiotics in support of rational use. However, further research is required to examine the impact of post-referral label changes on the clinical practice.

Modified Technique for the Visualization of C6/C7 in Lateral Cervical Spine Radiography

Introduction: In the Swimmer’s view, the C6 and C7 can be visualized as superimposed on the shoulders. This study aimed to explore the technique to demonstrate C1 to C7 in the lateral spine and improve the diagnostic value in that region. Material and Methods: An experimental study was carried out using a RANDO phantom to obtain images of the lateral cervical spine. Twelve radiographs were taken using different kVps at different centering points. The image quality of the radiographs was evaluated by two radiographers using the modified image quality criteria score sheet adapted from the Commission of European Communities on image quality. A dose area product meter was utilized to estimate the entrance surface dose (ESD); however, CALDose_X5 Monte Carlo software was used to estimate the effective dose. Results: The findings indicated that a higher centering point at 2 inches above the pinna of the ear can clearly visualize the lower cervical spine (C6/C7) and cervicothoracic junction (C7/T1). The results of the Kruskal-Wallis test revealed significant differences (p 0.05) in the ESD between different utilized centering points. The effective dose of the modified technique was reported to be lower, compared to that for the Swimmer’s view. Conclusion: The modified lateral technique can be used to replace the Swimmer’s view to adequately demonstrate the lower cervical spine and cervicothoracic junction with a lower radiation dose while not harming the patient due to movement during positioning.

Metallic Contamination of the Muscles of Three Fish Species from the Moulouya River (Lower Moulouya, Eastern Morocco)

This study introduces a spatiotemporal evaluation of the metallic contamination with three trace metals (mercury, lead, and cadmium) in the muscles of three fish species (Lepomis macrochirus, Barbus callensis, and Barbus nasus), of which the samples were taken from three stations in the Moulouya River: the confluence of the Moulouya River and the Sebra River (station 1), the neighbourhood of the farms in the region of Aklim downstream from confluence of Lakhmis river (station 2), and the level of ancient bridge of Ras El Ma-Moulouya (station 3), during the period from July 2017 to May 2018. The results have allowed us to highlight rather high contents of lead and mercury in the fish muscles, mainly in station 1, which receives domestic and industrial discharges. The contents of cadmium in all fish species in different stations are very low. Moreover, all concentrations assessed in different fish species do not exceed the maximum limit recommended by European Community (EC) Commission Regulation No. 1881/2006.

Recycling of REMS and removal of toxic metals from fluorescent and CRT waste: a review

Fluorescent lamp and cathode ray tube (CRT) waste considered as hazardous waste by commission of European communities and resource conservation and recovery act (RCRA). Due to the presence of mercury and lead in fluorescent waste and cathode ray tube waste, it is highly toxic for environment. Simultaneously, these wastes are also a vital source of different rare earth elements (REEs) such as Y, Eu, Ce, Tb and La. REEs are the most critical resources in the development of both traditional and high-tech industries all over the world. In order to prevent the misuse of natural resources, recycling of REEs from fluorescent and CRT waste is an effective step for accelerating the sustainable use of resources and protect environmental pollution from mining. So, recovery of REEs as well as removal of contaminated hazardous metals such as Hg and Pb from waste is a challenging task. Many researchers in the last few years focused on the development of different process such as solvent extraction, selective leaching, and precipitation for recovery of rare earth elements as well as the removal of toxic metal from waste. Particularly recoveries of yttrium and europium metals are the main interest of many researchers due to huge application in CFL bulbs and CRT tubes. Selective leaching of Y and Eu can be obtained in dilute acid solution with moderate temperature. Dissolution of Pb in leaching process can be avoided by leaching with H2SO4 as it forms insoluble sulfate. While coming to solvent extraction, three major classes of conventional extractantshavebeen used for extraction of REEs such as cation exchanger, solvating extractants and anion exchangers. The use of ionic liquids instead of conventional extractantsismore interesting in modern research because of their high thermal stability, nontoxic and high extraction ability. They are used for effective recovery of REEs from e-waste.

PMU107 INSIGHTS INTO REIMBURSEMENT RATES AND TIMELINES FOR ORPHAN DRUGS IN IRELAND

To gather insights into reimbursement rates and timelines for orphan drugs appraised by the National Centre for Pharmacoeconomics (NCPE). The European Commission's Community Register of orphan medicinal products for human use was cross-checked against appraisals on the NCPE website to identify orphan drugs that have been evaluated by the NCPE. The Health Services Executive (HSE) website was also searched for reimbursed drugs and cross-checked with NCPE assessments. The data from the identified evaluations were extracted and analysed in Excel. Between 2010 and 2019, 86 appraisals of 70 drugs were conducted by the NCPE. The majority were for non-cancer drugs (n=47, 54.7%) and in adults (n=58; 67.4%). Only 7 (8.1%) did not require a full pharmacoeconomic evaluation. In 18 (20.9%) instances the manufacturer did not provide a full pharmacoeconomic submission as requested. Of 68 completed appraisals, only 5 (4.7%) were positive recommendations, of which at least two required confidential price negotiations. The HSE approved another 34 drugs after confidential price negotiations (at least 22; 64.7%), the majority being cancer drugs (n=19; 55.9%). Average time from completion of the reimbursement process (either from the end of the Rapid Review or full pharmacoeconomic evaluation, whichever was the last assessment step) was 337 days (SD = 219) for cancer drugs, and 449 days (SD = 282) for non-cancer drugs. 8 drugs did not complete a full pharmacoeconomic evaluation, but was recommended by the HSE, on average after 495 days (SD = 330). Orphan drugs are extremely unlikely to be recommended by the NCPE, but are more likely to be recommended by the HSE. Manufacturers making submissions to Ireland should expect to discuss commercial discounts to secure reimbursement. Low positive recommendation rates by the NCPE, requirements for price negotiations and time to positive reimbursement with the HSE may deter manufacturers from making orphan drug submissions.

Evaluation of the Influence of Exposure Index on Image Quality and Radiation Dose

Introduction: The introduction of digital radiography has led to a significant problem in terms of dose creep. To address this problem, manufacturers have established a set of exposure indicators (EI) as a feedback mechanism to safeguard against overexposure. The EI is the measure of incident exposure to the detector that is directly proportional to the signal-to-noise ratio and can be related to image quality. The aim of this study was to evaluate the influence of EI on image quality and radiation dose for the posterior anterior (PA) chest radiography. Material and Methods: This study was conducted in three phases, namely pre-optimization, experimental, and post-optimization. A total of 60 patients that could fulfill the inclusion and exclusion criteria for the PA chest radiography were recruited. The radiographic technical parameters, dose area product, and EI were recorded. Radiographs were printed and evaluated by two recruited radiologists using the modified evaluation criteria established by the Commission of European Communities in 1996. Results: Statistical analysis using Spearman’s Rho Correlation showed an insignificant relationship between EI and image quality for the PA chest radiography (p >0.05). Conversely, there was a significant relationship between EI and radiation dose (p <0.05). Conclusion: TheEI can be used as an indirect measure of image quality and radiation dose. The EI does not directly determine image quality since the radiographic technique and parameters used can affect image quality. Although EI can be used as a measure of radiation dose, it cannot provide an accurate measurement of the radiation received by the patient.

Indoor air quality assessment of Federal University Dutse Library North West, Nigeria

The present study was aimed at evaluating the number of bacteria and fungi in the indoor environment of Federal University Dutse Library. The sampling site was located in the University main reading room. Forty (40) air samples were collected in the month of June 2018. Air samples comprising of twenty (20) for bacteria and twenty (20) for fungi were taken twice a day; in the morning and afternoon. All the samples were analyzed for the concentration of bacteria and fungi using plate count method. The average bacterial and fungal counts in the library were found to be 240.10 CFU/m 3 and 280.60 CFU/m 3 respectively and ranged from 132-345 CFU/m 3 for bacteria and 180-416 CFU/m 3 for fungi respectively. Having subjected the generated results to statistical analysis (T-test at 95% confidence limit), there was no significant difference between microbial loads recorded for bacteria and fungi (p-value=0.000). However, the mean microbial concentration of the library indoor air was within a range which indicates intermediate level of contamination according to the guidelines established in 1993 by the European Community Commission. It is therefore recommended that the surfaces of the library should be kept clean and dry, as the wet condition in the library can cause growth of pathogenic microorganisms. Again, a follow up study is required with a view to detecting seasonal variations of the indoor microbial counts of the library. Keywords: Indoor air quality, pollution, bacterial counts, fungal counts

The sanitation of farm animal manure from parasites

Οι κοπροσωροί που συγκeντρώνονται στις κτηνοτροφικές και πτηνοτροφικές eκμeταλλeύσeις μπορeί να αποτeλέσουν eστίeς μeτάδοσης παρασιτικών νοσημάτων και αιτία για την υποβάθμιση του πeριβάλλοντος. Στην παρούσα eργασία παρουσιάζονται οι διάφορeς μέθοδοι διαχeίρισης των κοπροσωρών που τις καθιστούν υγeιονομικά και πeριβαλλοντολογικά ασφαλeίς. Eπί πλέον, παρουσιάζeται το νομικό πλαίσιο σe eθνικό και eυρωπαϊκό eπίπeδο που διέπeι τη διαχeίριση και διάθeση των κοπροσωρών.

Patent statistics at the commission of the european communities

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Corporatism and Industrial Democracy: The Social Origins of Present Forms and Methods in Britain and Germany (1977)

This paper, written in 1977, analyses historical differences in the social aspects of industrialization in Britain and Germany. These are seen as relevant to an understanding of industrial relations in these countries and as to why the particular forms taken by developments of ‘industrial democracy’ in the two countries will continue to differ in significant ways. Deep-rooted institutions, values, traditions, and dispositions to act in certain ways rather than others, affect the wish and capacity to alter direction. This is relevant to the discussion within the European Community about legislation in employee participation. The European Community Commission argues that industrial and commercial growth; cross-frontier movements of companies, capital, and employees; and economic and monetary union require organized convergence towards ‘a common structural foundation’ throughout the Community. A structure of employee participation is seen as one important element of this convergence. But given the divergent historical legacies of the member-states, how far the Commission’s thrust towards uniform economic and social structures is likely to succeed is problematical.

Discriminating Oat and Groat Kernels from Other Grains Using Near‐Infrared Spectroscopy

Oats and groats can be discriminated from other grains such as barley, wheat, rye, and triticale (nonoats) with near‐infrared spectroscopy. The two instruments tested herein were the manual version of the United States Department of Agriculture–Agricultural Research Service single‐kernel near‐infrared (SKNIR) instrument and the automated QualySense QSorter Explorer high‐speed sorter, both used in similar near‐infrared spectral ranges. Three linear discriminate self‐prediction models were developed: 1) oats versus groats + nonoats, 2) oats + groats versus nonoats, and 3) groats versus nonoats. For all three models, the SKNIR instrument showed high correct classification of oats or groats (94.5–100%), which was similar to results of the QSorter Explorer at 95.0–99.4%. The amount of nonoats that were misclassified as oats or groats was low for both instruments at 0–0.2% for the SKNIR instrument and 0.8–3.7% for the QSorter Explorer. Linear discriminate models from independent prediction and validation sets yielded classification accuracies of 91.6–99.3% (SKNIR) and 90.5–97.8% (QSorter Explorer). Small differences in classification accuracy were attributed to processing speeds between the two instruments: 3 kernels/s for the SKNIR instrument and 35 kernels/s for the QSorter Explorer. This indicated that both instruments are useful for quantifying grain sample compositions of oat and groat samples and that both could be useful tools for meeting consumer demand for gluten‐free or low‐gluten products. Discrimination between grains will help producers and manufacturers meet various regulatory requirements. Examples include requirements such as those from the U.S. Food and Drug Administration and the Commission of European Communities, in which gluten‐free oats or other products can only be labeled as nongluten if they contain gluten at less than 20 ppm, the established safe consumption limit for people with celiac disease. The QSorter Explorer is currently being used to meet these requirements.

Trimethylamine oxide content and spoilage potential of New Zealand commercial fish species

ABSTRACTBreakdown of trimethylamine oxide (TMAO) during post-harvest storage contributes significantly to loss of seafood quality. We surveyed 51 New Zealand commercial fish species and determined white muscle tissue concentrations of TMAO and the TMAO-derived spoilage indices: trimethylamine nitrogen (TMA-N) and total volatile basic nitrogen (TVB-N). There were significant differences in the TMAO concentrations between fish of various genus and species. Values ranged between 8 and 789 mg/100 g for ray-finned fishes (Actinopterygii), and 262 and 789 mg/100 g for cartilaginous fishes. The distribution of TMAO was similar to that of Northern Hemisphere fish species. Deep water species had the highest concentrations of TMAO. Seasonal effects in tarakihi (Nemadactylus macropterus) and red gurnard (Chelidonichthys kumu) were studied and TMAO declined significantly over the summer months. TMA-N was typically below 2 mg/100 g and TVB-N concentrations did not exceed the limits set by the European Community (EC) Commission Regulation No. 1022/2008.

AN INVESTIGATION INTO CT RADIATION DOSE VARIATIONS FOR HEAD EXAMINATIONS ON MATCHED EQUIPMENT.

This study investigated radiation dose and image quality differences for computed tomography (CT) head examinations across centres with matched CT equipment. Radiation dose records and imaging protocols currently employed across three European university teaching hospitals were collated, compared and coded as Centres A, B and C from specification matched CT equipment models. Patient scans (n = 40) obtained from Centres A and C were evaluated for image quality, based on the visualisation of Commission of European Community (CEC) image quality criteria using visual grading characteristic (VGC) analysis, where American Board of Radiology examiners (n = 11) stated their confidence in identifying anatomical criteria. Mean doses in terms of CT dose index (CTDIvol-mGy) and dose length product (DLP-mGy cm) were as follows: Centre A-33.12 mGy and 461.45 mGy cm; Centre B -101 mGy (base)/32 mGy (cerebrum) and 762 mGy cm and Centre C-71.98 mGy and 1047.26 mGy cm, showing a significant difference (p ≤ 0.05) in DLP across centres. VGC analysis indicated better visualisation of CEC criteria on Centre C images (VGCAUC 0.225). All three imaging protocols are routinely used clinically, and image quality is acceptable in each centre. Clinical centres with identical model CT scanners have variously customised their protocols achieving a range of dose savings and still resulting in clinically acceptable image quality.

The factors affecting heavy metal levels in the muscle tissues of whiting (merlangius merlangus) and red mullet (mullus barbatus)

This study aims to determine heavy metal accumulation levels in the muscles tissues of two economically most important demersal fish species in the Eastern Black Sea, Turkey, red mullet (Mullus barbatus) and whiting (Merlangius merlangus), and evaluate the effects of fish species, sampling locations, fishing season and size groups on heavy metal accumulation levels. Chromium (Cr), manganese (Mn), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd) and lead (Pb) concentrations in fish muscle samples were measured with Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Co, Zn, As and Cd accumulation levels in both species differed significantly (P<0.05). The metal concentrations of muscle tissues of both species, in general, were higher during summer and autumn. In the study, the differences in concentrations levels of As and Pb in whiting, Co, Cu, and Pb in red mullet muscle tissues were significantly related to fishing locations. The results of metal concentrations were compared with various legal limits such as Turkish Food Codex (TFC 2011), European Communities Commission Regulation (EC 2006) and Food and Agriculture Organization (FAO 1983) and the obtained metal levels of fish muscle tissues of both species were found to be below the limit values which are a threat to human health.

New finding of Trichinella britovi in a European beaver (Castor fiber) in Latvia

We report the first finding of Trichinella britovi in a European beaver. In Latvia, beaver is a common game animal and frequently used in human diet. A high prevalence of Trichinella infections in Latvia is present in the most common hosts-carnivores and omnivores. In total, 182 European beaver muscle samples were tested for Trichinella larvae accordingly to the reference method of European Communities Commission Regulation (EC) No. 2075/2005 (2005). Trichinella britovi larvae were detected in one animal (prevalence 0.5%; intensity 5.92 larvae per gram of muscle). This finding suggests that the consumption of European beaver meat can be a risk to human health. Further studies are needed in order to determine if the present observation represents an isolated individual case or low prevalence of Trichinella infection in beavers.

Metal contamination of home garden soils and cultivated vegetables in the province of Brescia, Italy: Implications for human exposure

BackgroundFor the past century, ferroalloy industries in Brescia province, Italy produced particulate emissions enriched in manganese (Mn), lead (Pb), zinc (Zn), copper (Cu), cadmium (Cd), chromium (Cr), iron (Fe), and aluminum (Al). This study assessed metal concentrations in soil and vegetables of regions with varying ferroalloy industrial activity levels. MethodsHome gardens (n=63) were selected in three regions of varying ferroalloy plant activity durations in Brescia province. Total soil metal concentration and extractability were measured by X-Ray Fluorescence (XRF), aqua regia extraction, and modified Community Bureau of Reference (BCR) sequential extraction. Unwashed and washed spinach and turnips cultivated in the same gardens were analyzed for metal concentrations by flame atomic absorption spectrometry. ResultsMedian soil Al, Cd, Fe, Mn, Pb, and Zn concentrations were significantly higher in home gardens near ferroalloy plants compared to reference home gardens. The BCR method yielded the most mobile soil fraction (the sum of extractable metals in Fractions 1 and 2) and all metal concentrations were higher in ferroalloy plant areas. Unwashed spinach showed higher metal concentrations compared to washed spinach. However, some metals in washed spinach were higher in the reference area likely due to history of agricultural product use. Over 60% of spinach samples exceeded the 2- to 4-fold Commission of European Communities and Codex Alimentarius Commission maximum Pb concentrations, and 10% of the same spinach samples exceeded 2- to 3-fold maximum Cd concentrations set by both organizations. Turnip metal concentrations were below maximum standard reference values. ConclusionsProlonged industrial emissions increase median metal concentrations and most soluble fractions (BCR F1+F2) in home garden soils near ferroalloy plants. Areas near ferroalloy plant sites had spinach Cd and Pb metal concentrations several-fold above maximum standard references. We recommend thorough washing of vegetables to minimize metal exposure.