Non-targeted analysis based on quantitative prediction and toxicity assessment for emerging contaminants in tire particle leachates.

Non-targeted analysis (NTA) has great potential to screen emerging contaminants in the environment, and some studies have conducted in-depth investigation on environmental samples. Here, we used a NTA workflow to identify emerging contaminants in used tire particle (TP) leachates, followed by quantitative prediction and toxicity assessment based on hazard scores. Tire particles were obtained from four different types of automobiles, representing the most common tires during daily transportation. With the instrumental analysis of TP leachates, a total of 244 positive and 104 negative molecular features were extracted from the mass data. After filtering by a specialized emerging contaminants list and matching by spectral databases, a total of 51 molecular features were tentatively identified as contaminants, including benzothiazole, hexaethylene glycol, 2-hydroxybenzaldehyde, etc. Given that these contaminants have different mass spectral responses in the mass spectrometry, models for predicting the response of contaminants were constructed based on machine learning algorithms, in this case random forest and artificial neural networks. After five-fold cross-validation, the random forest algorithm model had better prediction performance (MAECV = 0.12, Q2 = 0.90), and thus it was chosen to predict the contaminant concentrations. The prediction results showed that the contaminant at the highest concentration was benzothiazole, with 4,875 µg/L in the winter tire sample. In addition, the joint toxicity assessment of four types of tires was conducted in this study. According to different hazard levels, hazard scores increasing by a factor 10 were developed, and hazard scores of all the contaminants identified in each TP leachate were summed to obtain the total hazard score. All four tires were calculated to have relatively high risks, with winter tires having the highest total hazard score of 40,751. This study extended the application of NTA research and led to the direction of subsequent targeting studies on highly concentrated and toxic contaminants.

Assessment of the bioaccessibility of PAHs and other hazardous compounds present in recycled tire rubber employed in synthetic football fields.

Recycled tire crumb rubber (RTCR) surfaces contain harmful and carcinogenic substances, which can be ingested by the users of these facilities, mainly athletes and children. In this work, the potential in-vitro oral bioaccessibility of eighteen polycyclic aromatic hydrocarbons (PAHs) from RTCR employed as infill in synthetic football fields was studied in human synthetic body fluids (saliva, gastric, duodenal and bile), prepared according the Unified Bioaccessibility Method. Solid-phase extraction (SPE) using commercial sorbents and a new green material based on cork (cork industry by-product) were used to isolate the bioaccessible PAHs before gas chromatography-tandem mass spectrometry analysis. The method was optimized and validated attending the analytical figures of merit. The feasibility of cork biosorbent for the extraction of the compounds was demonstrated, as well as the suitability of the UBM method to perform the digestion with good precision. The application to real samples collected from football fields demonstrated the presence of 17 of the 18 target PAHs in the biofluids. Most volatile PAHs such as NAP, ACY, ACE, FLU, PHN and ANC, achieved the highest bioaccessibility percentage levels. The carcinogenic B[a]P was detected in 75 % of the samples at concentrations up to 2.5 ng g-1 (bioaccessible fraction). Children exposure assessment was carried out to identify potential risk. Other hazardous and environmentally problematic compounds such as N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD-quinone), recently related with the dead of coho salmon, and hexamethoxymethylmelamine (HMMM), among others, were also detected. This is the first study in which the bioaccesibility from real crumb rubber samples of 15 out of the 16 PAHs considered as priority pollutants by the United States Environmental Protection Agency (EPA) and the presence of 6PPD-quinone and HMMM in the bioaccessible fractions is reported.

Guayule (Parthenium argentatum A. Gray), a Renewable Resource for Natural Polyisoprene and Resin: Composition, Processes and Applications.

Natural rubber is an essential material, especially for plane and truck tyres but also for medical gloves. Asia ranks first in the production of natural rubber, of which the Hevea tree is currently the sole source. However, it is anticipated that this source alone will not be able to fulfill the growing demand. Guayule, a shrub native to northern Mexico and southern United States, may also contribute. This plant not only contains polyisoprene, but also resin, a mixture of lipids and terpenoids. This review summarizes various aspects of this plant, from the usage history, botanical description, geographical distribution and cultivation practices, down to polyisoprene and resin biosynthesis including their distribution within the plant and molecular composition. Finally, the main processes yielding dry rubber or latex are depicted, as well as the properties of the various extracts along with economic considerations. The aim is to provide a wide picture of current knowledge available about this promising crop, a good feedstock candidate for a multiple-product biorefinery.

Genomic technologies for Hevea breeding.

The commercial production of high quality natural rubber (NR) solely depends on Hevea brasiliensis Muell. Arg, (Para rubber tree) and accounts for >98% of total production worldwide. NR with its unique properties is an essential commodity for the automobile industry and its synthetic counterparts are in no way substitute to it. The rubber tree genome is very complex and plays an important role in delivering the unique properties of Hevea. But a lack of knowledge on the molecular mechanisms of rubber biosynthesis, disease resistance, etc., in elite clones of rubber still persists. Marker-assisted selection and transgenic techniques were proved to be advantageous in improving the breeding efficiency for latex yield, disease resistance, etc. The suppression subtractive hybridization (SSH), in the form of subtracted cDNA libraries and microarrays, can assist in searching the functions of expressed genes (candidate gene approach). Expressed sequence tags (ESTs) related to various metabolic aspects are well utilized to create EST banks that broadly represent the genes expressed in one tissue, such as latex cells, that assists in the study of gene function and regulation. Transcriptome analysis and gene mapping have been accomplished in Hevea at various stages. However, a selection criterion to delineate high yielding genotypes at the juvenile stage has not been accomplished so far. This is the main pit fall for rubber breeding apart from stock-scion interactions leading to yield differences among a clonally multiplied population. At least four draft genome sequences have been published on Hevea rubber, and all give different genome size and contig lengths-a comprehensive and acceptable genomic map remains unfulfilled. The progress made in molecular markers, latex biosynthesis genes, transcriptome analysis, chloroplast and mitochondrial DNA diversity, paternity identification through Breeding without Breeding (BwB), stimulated latex production and its molecular intricacies, molecular biology of tapping panel dryness, genomics for changed climates and genome mapping are discussed in this review. These information can be utilized to improvise the molecular breeding programs of Hevea in future.

Balancing Container Closure Integrity and Aesthetics for a Robust Aseptic or Sterile Vial Packaging System.

Container closure integrity (CCI) is one of the requirements for a sterile packaging system. For vial-based systems, the capping process is a critical step in creating and ensuring an adequate seal with acceptable CCI. Container closure integrity tests (CCITs) such as the dye ingress and the helium leak rate are two methods among many that, in the appropriate scenario, help to challenge this required attribute. The use of locked-in stopper compression (compression under the crimp seal post capping) enables correlation of these methods to CCI and seal quality. In fact, the overall acceptability of a seal can be evaluated using quantitative and qualitative methods. Usually lost in these assessments is the existence of seal cosmetics as an essential additional seal quality attribute. Unacceptable cosmetic quality can have a major impact on manufacturing (reduced batch output, high yield cost, etc.) and user (perceived low quality, brand image, potential injury, etc.) experiences. Interestingly, the aesthetics of a seal is also impacted by the capping process which is quite complicated because the acceptance criteria for aesthetics of a seal is subjective. Ultimately, this affects commercial manufacturing efficiency and CCI. Here, we present a simple methodology for package selection and evaluated multiple package configurations using locked-in stopper compression (through residual seal force, RSF) measurements and seal aesthetics analyses (using a semi-quantitative aesthetics scale). The integrity of the seals was analyzed using multiple CCIT methods. We determined that component dimensions such as the seal length play a major role in obtaining proper seal aesthetics and integrity. This can ultimately enable the selection of robust packaging components that provide an adequate range of manufacturing conditions without cosmetic defects. A failure to do this could result in high rejects during drug product visual inspection culminating in low batch yield, high costs or could pose harm to patients if suitable CCI is not achieved.LAY ABSTRACT: One common container closure system for parenteral drug products includes a glass vial, rubber stopper, and aluminum crimp seal. The capping process, in which the elastomeric closure is compressed against the vial by means of an aluminum crimp seal, is key to ensuring an optimal seal from both an aesthetic and CCI perspective. Ensuring a robust capping process must include a deep and necessary understanding of the interconnection between the selected components, desired aesthetics of the seal, stopper compression, residual seal force, and CCI; the way in which the capper is configured (sealing parameters) will play a part in addition to the "style" used in manufacturing. Previous published studies have focused on capping process controls to only ensure CCI. Here, we present a useful methodology for selecting appropriate components and capping process parameters using a scaled-down approach to achieve elegant seal quality and CCI simultaneously. Dimensional analysis and capping design of experiments (DOEs) were conducted on lab-scale equipment that was representative of commercial configurations. The seals made from these studies were analyzed using residual seal force, helium leak, and dye ingress methods. The results and their implications were discussed with regard to the operating principle of the rail-type capping machine.

Rubber Accelerators in Medical Examination and Surgical Gloves.

BACKGROUND: Rubber accelerators play a significant role in glove-related occupational contact dermatitis, especially among health care workers. Currently, there is limited information readily available outlining the accelerators used in specific medical examination and surgical gloves. OBJECTIVE: The aim of this study was to ascertain the accelerators used in medical examination and surgical gloves for major glove manufacturers within the United States. METHODS: An initial Internet-based search was performed to establish relevant manufacturers and product lines, with subsequent inquiry with each corresponding company regarding accelerators used in each medical and surgical glove line. RESULTS: Eleven glove manufacturers were identified and contacted. Responses were obtained from all manufacturers, but because of legal limitations, changes in product lines, or inability to supply necessary data, only 8 companies were able to be included in the final analysis, totaling data for 190 gloves. Carbamates were the most common accelerator, used in 90.5% (172/190) of gloves, whereas thiurams were used in only 11 gloves (5.8%). Eight companies surveyed are now advertising and offering touted accelerator-free gloves. CONCLUSIONS: Accelerators are used in most examination and surgical gloves; however, manufacturers are now expanding their product offerings to include accelerator-free options.

Comprehensive multipathway risk assessment of chemicals associated with recycled ("crumb") rubber in synthetic turf fields.

BACKGROUND: Thousands of synthetic turf fields in the US are regularly used by millions of individuals (particularly children and adolescents). Although many safety assessments have concluded that there are low or negligible risks related to exposure to chemicals found in the recycled rubber used to make these fields, concerns remain about the safety of this product. Existing studies of recycled rubber's potential health risks have limitations such as small sample sizes and limited evaluation of relevant exposure pathways and scenarios. OBJECTIVE: Conduct a comprehensive multipathway human health risk assessment (HHRA) of exposure to chemicals found in recycled rubber. METHODS: All available North American data on the chemical composition of recycled rubber, as well as air sampling data collected on or near synthetic turf fields, were identified via a literature search. Ingestion, dermal contact, and inhalation pathways were evaluated according to US Environmental Protection Agency (US EPA) guidance, and exposure scenarios for adults, adolescents, and children were considered. RESULTS: Estimated non-cancer hazards and cancer risks for all the evaluated scenarios were within US EPA guidelines. In addition, cancer risk levels for users of synthetic turf field were comparable to or lower than those associated with natural soil fields. CONCLUSIONS: This HHRA's results add to the growing body of literature that suggests recycled rubber infill in synthetic turf poses negligible risks to human health. This comprehensive assessment provides data that allow stakeholders to make informed decisions about installing and using these fields.

Accelerator-free gloves as alternatives in cases of glove allergy in healthcare workers.

BACKGROUND: Accelerators in rubber gloves constitute an important group of contact allergens, particularly in healthcare workers. OBJECTIVES: To assess the efficacy of accelerator-free medical gloves in the secondary prevention of allergic contact dermatitis caused by rubber accelerators in healthcare workers. METHODS: Nine healthcare workers with hand eczema were advised to use accelerator-free rubber gloves after a diagnosis of allergic contact dermatitis caused by rubber accelerators. RESULTS: Switching from conventional medical single-use gloves containing accelerators to accelerator-free medical gloves led to improvement in all cases, and more than two-thirds of the patients were completely free of symptoms. CONCLUSION: The use of accelerator-free medical gloves can be an effective alternative in healthcare workers who are allergic to rubber accelerators.

Development of an Economical Method to Reduce the Extractable Latex Protein Levels in Finished Dipped Rubber Products.

Natural rubber latex (NRL) allergy is caused by the extractable latex proteins in dipped rubber products. It is a major concern for the consumers who are sensitive to the allergenic extractable proteins (EP) in products such as NRL gloves. Objective of this research was to develop an economical method to reduce the EP in finished dipped NRL products. In order to reduce the EP levels, two natural proteases, bromelain from pineapple and papain from papaya, were extracted and partially purified using (NH4)2SO4. According to the newly developed method, different glove samples were treated with a 5% solution of each partially purified enzyme, for 2 hours at 60°C. Residual amounts of in treated samples were quantified using the modified Lowry assay (ASTM D5712-10). Bromelain displayed a 54 (±11)% reduction of the EP from the dipped rubber products, whereas it was 58 (±8)% with papain. These results clearly indicate that the selected natural proteases, bromelain, and papain contribute significantly towards the reduction of the total EP in finished NRL products. Application of bromelain enzyme for the aforementioned purpose has not been reported up to date, whereas papain has been used to treat raw NRL towards reducing the EP.

Identification of UV-absorbing extractables from rubber closures used in containers of injectable powder and safety assessment of leachables in the drug.

Rubber closures have been of great concern to regulatory authorities on account of their potential safety risks to patients. The aim of our work is to provide part of data about the compatibility of the injectable powder and its packaging materials for the drug registration. In this report, methodologies were established to study the system of the preparation. Firstly, three major extractables were isolated by semi-preparative HPLC method combined with silica gel-based chromatographic methods. NMR spectra including 1D NMR (1H, 13C, DEPT135) and 2D NMR (COSY, HSQC, HMBC) were introduced to identify the extractables, besides HPLC, GC-MS, ESI-MS/MS and HRMS. The extractables were determined to be N-(2-(2,2,4,4-tetramethylcyclohexyl)allyl) benzo[d]thiazol-2-amine (1), 2,6-Di-tert-butyl-4-methylphenol (2) and sulfur (3) respectively. Then, to address safety concerns, approaches including QSAR analysis, the TTC and comprehensive literature evaluation methods to toxicological safety evaluation of the target compounds were established, where the safety threshold such as TTC and PDE values were developed. Finally, the migration testing of the extractables were performed to assess the leaching behavior of the rubber closures. An optimized analysis method was proposed using SPE and HPLC with an ultraviolet detector, which demonstrated good linearity, acceptable accuracy and precision. The levels of the target compounds in the powder were measured and the calculated worst case exposure of extractable 2 exceeded the TTC limit of 1.5µg/day, indicating that the products may possess potential health risks to patients. In contrast to previous studies, various NMR techniques, which were rarely applied to identify unknown extractables from rubber closures in the literature, were discussed for the structural elucidation of rubber closures extractables. Among the target compounds, extractable 1 was a new compound, whose isolation and structural elucidation were first reported here.

Is insulin diluted when stored in water?

BACKGROUND: Insulin storage is a challenge in resource-poor countries. In Uganda, patients were noted to store insulin vials by submerging them in water. OBJECTIVE: To examine whether withdrawing insulin from a vial without adding air back causes a vacuum which allows water to enter the vial, resulting in insulin dilution. METHODS: Seven hundred units of insulin were withdrawn from forty 10 mL vials of 100 units/mL insulin [20 neutral protamine hagedorn (NPH), 20 regular]. In half, air was added back. The vials were weighed (baseline). Half of the vials (10 with added air, 10 without) were submerged in water for 24 h and then air-dried for 24 h. Vials that were not submerged sat at room temperature for 48 h. All vials were weighed 48 h from baseline. RESULTS: Addition of air did not impact the change in weight after submersion (air added: -0.002 ± 0.001 g or -0.2 ± 0.1 unit; no air added: -0.003 ± 0.000 g or -0.3 ± 0 unit, p = 0.57). In a subset of vials in which an additional 240 units were withdrawn before submersion for another 24 h, there was still no difference in weight change in those vials with air added (p = 0.2). CONCLUSION: Withdrawing insulin from a vial without adding air did not result in uptake of water or dilution of insulin in the submerged vial, although it made drawing up the insulin easier. This study did not address the larger concern of bacterial contamination of the rubber stopper during water storage.

Formaldehyde and heavy metal migration from rubber and metallic packaging/utensils in Korea.

The aim of this study was to determine the non-intentionally added substances--formaldehyde and trace metals--at 4% acetic acid conditions in rubber and metallic packaging/utensils. The temperature effect on migration in rubber and metallic packaging/utensils was monitored at 60 °C and 100 °C under acidic (pH < 3) circumstances. The concentrations were: formaldehyde--23.1 µg kg⁻¹, lead--13.41 µg kg⁻¹, cadmium--0.15 µg kg⁻¹, total arsenic--2.02 µg kg⁻¹ and nickel--2.92 µg kg⁻¹ at 60 °C and formaldehyde--148.9 µg kg⁻¹, lead--17.04 µg kg⁻¹, cadmium--0.14 µg kg⁻¹, total arsenic--7.25 µg kg⁻¹ and nickel--8.7 µg kg⁻¹ at 100 °C. A significant difference was noticed in formaldehyde and total arsenic between both temperatures (p < 0.01), which was not present in other trace metals. In conclusion, formaldehyde and total arsenic were more sensitive with cooking temperature than the other metals.

Assessment of 99mTc-succimer residual activity using inert nonreactive syringes.

UNLABELLED: It has been widely reported that (99m)Tc-succimer adsorbs to plastic syringes significantly (up to 50%), often resulting in a lower administered dose than intended or inaccurate dosing. This adsorption rate is especially problematic in the pediatric population. To improve (99m)Tc-succimer dosing, we compared the adsorption of (99m)Tc-succimer with 2 types of syringes: silicone-coated syringes with nonlatex rubber on the plunger and inert nonreactive syringes with no silicone coating and no rubber on the plunger. METHODS: (99m)Tc-succimer kits were compounded according to the manufacturer's instructions. (99m)Tc-succimer doses (37-185 MBq) were drawn into 3-mL (silicone-coated or inert nonreactive) syringes in a 1-mL volume. Thirty min, 1 h, 2 h, and 4 h later, the syringes were assayed in a dose calibrator and assayed again after being emptied and rinsed with saline. In addition, we examined the data collected from 129 (99m)Tc-succimer doses administered in a pediatric department, in which 52 were dispensed in silicone-coated syringes and 77 were dispensed in inert nonreactive syringes. The doses were assayed immediately before and after injection. The syringes were flushed with normal saline. RESULTS: The labeling efficiency of the (99m)Tc-succimer kits was more than 95%. Residual activity left in the inert nonreactive syringes was 0.73% (SD, ±0.18%), which was significantly lower than the activity left in the silicone-coated syringes, 20.9% (SD, ±5.6%; P < 0.0001). The extent of adsorption did not change significantly between 30 min and 4 h of incubation. The clinical data showed that the residual activity was 30.6% (SD, ±12.5%) from doses dispensed in silicone-coated syringes and 6.38% (SD, ±2.95%) from doses dispensed in inert nonreactive syringes (P < 0.001). CONCLUSION: The inert nonreactive syringes had significantly less residual of (99m)Tc-succimer than silicone-based syringes, making it possible to accurately administer calculated doses of (99m)Tc-succimer to pediatric patients.

Technical inventions that enabled artificial infant feeding.

Artificial feeding of infants, called hand-feeding, was unsafe well into the 19th century. This paper aims to identify technical innovations which made artificial feeding less dangerous. In rapid succession from 1844 to 1886, the vulcanization of rubber, production of rubber teats, cooling machines for large-scale ice production, techniques for milk pasteurization, evaporation and condensation, and packing in closed tins were invented or initiated. Remarkably, most of these inventions preceded the discovery of pathogenic bacteria. The producers of proprietary infant formula made immediate use of these innovations, whereas in the private household artificial feeding remained highly dangerous - mostly because of ignorance about bacteria and hygiene, and partly because the equipment for safe storage, transport, preparation and application of baby food was lacking.

Artificial-turf playing fields: contents of metals, PAHs, PCBs, PCDDs and PCDFs, inhalation exposure to PAHs and related preliminary risk assessment.

The artificial-turf granulates made from recycled rubber waste are of health concern due the possible exposure of users to dangerous substances present in the rubber, and especially to PAHs. In this work, we determined the contents of PAHs, metals, non-dioxin-like PCBs (NDL-PCBs), PCDDs and PCDFs in granulates, and PAH concentrations in air during the use of the field. The purposes were to identify some potential chemical risks and to roughly assess the risk associated with inhalation exposure to PAHs. Rubber granulates were collected from 13 Italian fields and analysed for 25 metals and nine PAHs. One further granulate was analysed for NDL-PCBs, PCDDs, PCDFs and 13 PAHs. Air samples were collected on filter at two fields, using respectively a high volume static sampler close to the athletes and personal samplers worn by the athletes, and at background locations outside the fields. In the absence of specific quality standards, we evaluated the measured contents with respect to the Italian standards for soils to be reclaimed as green areas. Zn concentrations (1 to 19 g/kg) and BaP concentrations (0.02 to 11 mg/kg) in granulates largely exceeded the pertinent standards, up to two orders of magnitude. No association between the origin of the recycled rubber and the contents of PAHs and metals was observed. The sums of NDL-PCBs and WHO-TE PCDDs+PCDFs were, respectively, 0.18 and 0.67×10(-5) mg/kg. The increased BaP concentrations in air, due to the use of the field, varied approximately from <0.01 to 0.4 ng/m(3), the latter referring to worst-case conditions as to the release of particle-bound PAHs. Based on the 0.4 ng/m(3) concentration, an excess lifetime cancer risk of 1×10(-6) was calculated for an intense 30-year activity.

Production of activated carbons from waste tire--process design and economical analysis.

The process design and economic analysis of process plants to produce activated carbons from waste tires and coal have been performed. The potential range of products from each process has been considered, namely for waste tire--pyro-gas, active carbon, carbon black and pyro-oil; for coal--pyro-gas and active carbons. Sensitivity analyses have been carried out on the main process factors; these are product price, production capacity, total production cost, capital investment and the tipping fee. Net present values for the two plants at various discount factors have been determined and the internal rates of return have been determined as 27.4% and 18.9% for the waste tire plant and the coal plant, respectively.

Environmental assessment of 5-ethylidene-2-norbornene using modeled and measured fate and effects results.

Several predictive models were used to assess aquatic exposure, persistence (P) and potential for long-range transport (LRT) of 5-ethylidene-2-norbornene (ENB). Such estimations are components of the assessment process for persistent, bioaccumulative and toxic (PBT) substances, which are also referred to as persistent organic pollutants (POPs). An ecological exposure assessment for ENB from manufacturing activities was conducted based on physical/chemical properties, monitoring data, and degradation, transport and distribution estimates. Based on the results of several model predictions, chronic exposure of aquatic organisms is not expected, due to the anticipated residence time of ENB in aquatic ecosystems. These modeled results consistently predict ENB does not present the potential to persist in the environment. Volatilization from water to the air is calculated to occur at a relatively rapid rate for ENB based on its Henry's Law constant. Once in the air, ENB is expected to degrade rapidly due to oxidation by hydroxyl radicals and ozone based on calculated atmospheric half-lives of 57 and 27 min, respectively. Additionally, ENB is not predicted to undergo long-range transport based on the short atmospheric half-life due to oxidation by hydroxyl radicals and ozone. Additionally, based on predicted exposure from site-specific emission using the EPA model EFAST, ENB is not expected to reach concentrations of concern for chronic aquatic toxicity endpoints.

Adsorption of anionic surfactant by a low-cost adsorbent.

This study was undertaken to evaluate the efficiency of rubber granule, a low-cost adsorbent for the removal of sodium dodecyl sulfate (SDS) that is a representative member of anionic surfactant (AS). In the batch experiments conducted at an initial concentration range of 2-6 mg/l, it was found that the rubber granules selected could remove SDS from water up to 90%. Kinetic profiles were developed for various conditions. Effects of adsorbent size, initial adsorbate concentration and adsorbent dose, pH, Ca2+ ion concentration, Fe2+ ion concentration, Cl- ion concentration, and ionic strength on the adsorption of SDS on rubber granules were studied. The adsorption isotherm studies were also conducted.

Iodinated natural rubber latex: preparation, characterisation & antibacterial activity assessment.

Natural Rubber (NR) in both its latex and dried form was treated with iodine to make it antibacterial in nature. The NR latex was dried and washed, dissolved in toluene, iodinated and cast into films. In a different approach, NR in its latex form (emulsion) was blended with aqueous solution of povidone-iodine complex (PVP-I) and films were cast. Phase separation of PVP-I was observed in the films prepared using NR latex; whereas the film prepared using NR solution in toluene and molecular iodine were homogeneous, transparent light brown. Solubility assessment of the films revealed that unlike pure NR, the iodinated NR failed to go into solution completely. The films obtained from both the approaches were evaluated for release of iodide ions. On immersion in water, PVP-I blended latex did not retain iodine while sustained release of iodide ion was observed in case of dried NR dissolved in toluene and treated with iodine. The FT-IR spectra of the iodinated films revealed that iodine attaches covalently to the double bonds in the isoprene units of NR. The films were also evaluated for their antibacterial properties and it was observed that the films prepared from both the approaches, acquired antimicrobial properties.