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PubMedDate not supplied

Does surgical technique influence cataract surgery contamination?

PURPOSE: To compare cataract surgery contamination rates in large-incision extracapsular cataract extraction (ECCE) and phacoemulsification (PE), we studied 65 cases prospectively. METHODS: Thirty-five cases were operated by large-incision ECCE (Group I) and 30 by PE (Group II). Conjunctival swab cultures were taken immediately before surgery and anterior chamber aspirate was taken for culture upon completion of surgery for each case. RESULTS: Anterior chamber cultures were positive in 22.8% of the cases in group I and 23% in Group II. Frequencies of contamination in each group were no different (x2: 0.22, p>0.05). When the contaminations were evaluated in relation to operating time, prolongation of the operating time raised the contamination rate in Group I (p<0.05) but not in Group II (p>0.05). Silicone and PMMA intraocular lenses (IOL) were tested to see whether they had any additional risk of contamination. The frequencies of contaminated silicone IOL implanted cases (6/26) and contaminated PMMA IOL implanted cases (8/39) were similar (x2: 0.36, p>0. 05). CONCLUSIONS: Although the architecture of the incision and irrigation dynamics provided an advantage to the PE technique as the operating time became longer, routine PE was not superior to classical ECCE with respect to contamination when performed in the same circumstances. Prolonging the operating time raised the contamination rate in classical ECCE.

Aqueous Humor↗

PubMed2004

Effect of saliva contamination on induced sputum cell counts, IL-8 and eosinophil cationic protein levels.

Excessive salivary contamination of induced sputum samples prevents the satisfactory examination of lower airway inflammation. The effects of salivary contamination on different sputum fluid phase measures and the levels of salivary contamination preventing analysis are not defined. The present study sought to examine this by investigating the effect of increasing salivary contamination on induced sputum samples. Sputum and saliva samples from subjects with asthma and healthy controls were collected, and treated with dithiothreitol (DTT). Saliva was then added to aliquots of dispersed sputum in increasing proportions (0% to 100%). The effect of increasing saliva contamination was assessed on sputum total cell count, viability, differential cell count and fluid phase levels of interleukin (IL)-8, eosinophil cationic protein (ECP) and total protein. The addition of saliva to induced sputum reduced total cell counts and absolute cell counts but did not change the differential cell count. Levels of fluid phase ECP and IL-8 were significantly reduced with increased salivary contamination. There was a progressive reduction in ECP and IL-8, which reached significance at 70% and 80% saliva contamination, respectively. IL-8 levels corrected for total protein showed no change with increasing saliva concentrations. Induced sputum differential cell counts expressed as the proportion of nonsquamous cells are robust measures that are not influenced by salivary contamination. Studies reporting total and absolute cell counts and fluid phase mediator levels require control for squamous contamination.

Adult↗

PubMed1996

[An improved method for estimating daily intake of environmental contaminants using Monte-Carlo simulation].

We previously developed a new method for estimating intakes of environmental contaminants, called Estimated Ecological Daily Intake (EEDI), which is based on food consumption data. This method accurately estimates the intakes of food additives and contaminants and provides rough estimates of averages and distribution curves for the target population. By this method, we originally considered only food consumption, but did take into account the contamination level of each food article. Therefore, we attempted to improve EEDI by incorporating contamination levels of foodstuffs. Practically, we developed an improved Estimated Ecological Daily Intake estimation method for the daily intake of food contaminants and additives, and estimated daily intake of environmental contaminants based on food consumption data of 159 female volunteers, assuming that the contamination level follows Poisson distribution. The results obtained are as follows: 1) Estimated intakes were found to be accurate enough to obtain important values of distribution, such as mean, maximum value, mode, and median, which could be used to determine a standard. 2) Comparing the distribution of the estimated intakes, with that of intakes estimated by the fixed contamination level, the class-containing mode became lower and the class-containing the maximum value became higher. 3) This method was shown to provide information on the risk or probability of exceeding tolerable intake due to excessive food consumption or eating highly contaminated foods.

Eating↗

PubMed2006

Reproduction, embryonic development, and maternal transfer of contaminants in the amphibian Gastrophryne carolinensis.

Although many amphibian populations around the world are declining at alarming rates, the cause of most declines remains unknown. Environmental contamination is one of several factors implicated in declines and may have particularly important effects on sensitive developmental stages. Despite the severe effects of maternal transfer of contaminants on early development in other vertebrate lineages, no studies have examined the effects of maternal transfer of contaminants on reproduction or development in amphibians. We examined maternal transfer of contaminants in eastern narrow-mouth toads (Gastrophryne carolinensis) collected from a reference site and near a coal-burning power plant. Adult toads inhabiting the industrial area transferred significant quantities of selenium and strontium to their eggs, but Se concentrations were most notable (up to 100 microg/g dry mass). Compared with the reference site, hatching success was reduced by 11% in clutches from the contaminated site. In surviving larvae, the frequency of developmental abnormalities and abnormal swimming was 55-58% higher in the contaminated site relative to the reference site. Craniofacial abnormalities were nearly an order of magnitude more prevalent in hatchlings from the contaminated site. When all developmental criteria were considered collectively, offspring from the contaminated site experienced 19% lower viability. Although there was no statistical relationship between the concentration of Se or Sr transferred to eggs and any measure of offspring viability, our study demonstrates that maternal transfer may be an important route of contaminant exposure in amphibians that has been overlooked.

Amphibians↗

PubMed1997

Contamination of bone allografts: analysis of incidence and predisposing factors.

We analysed the bacterial contamination of 1999 bone allografts retrieved from 200 cadaver donors under sterile operating conditions. The effect of various factors on the relative risk of contamination was estimated using a multiple logistic regression model. Organisms of low pathogenicity were cultured from 50% of the grafts and of high pathogenicity from 3%. The risk of contamination with low pathogenic organisms (mainly skin commensals) increased by a factor of 1.6 for each member added to the procurement team. The risk of contamination with high pathogenic organisms (mainly contaminants from the gastrointestinal tract) was 3.4 times higher in donors with a traumatic cause of death and 5.2 times higher in those with a positive blood culture. Preceding organ procurement did not significantly influence the risk of contamination. Rinsing the graft with an antibiotic solution was not an effective decontamination method. The major source of contamination is exogenous and is strongly influenced by the procurement team. Contamination from endogenous sources can be controlled by donor selection. We discuss methods that can be used to decrease contamination and the rate of discarding of bone allografts.

Anti-Bacterial Agents↗

PubMed2003

Incidence of clostridial contamination in donors' musculoskeletal tissue.

Reports of infection by Clostridium sordellii associated with allograft transplantation have generated considerable interest. We report our experience in recognising clostridial contamination in cadaver donors of musculoskeletal tissue. Tissues obtained from 795 consecutive donors were excised using standard surgical techniques. Samples of blood and bone marrow were also obtained. Donors with clostridia recovered from any site were matched with the preceding donor without clostridia as a procedural and environmental control. The histories of the donors were analysed to determine which variables had a relationship to contamination by running a contingency table and chi-squared test on the variables against the event of a donor being contaminated. Sixty-four donors (8.1%) had clostridia, most commonly C. sordellii. Clostridia were grown from the blood, marrow and tissue samples of 52, 37 and 30 donors, respectively. In eight cases, they were cultured from the tissue samples alone. There was no significant difference in age or gender between the contaminated donors and the control group. Open wounds were more common in control than in contaminated subjects, but only death by drowning in the contaminated group was statistically significant (p = 0.02). The time between death and the excision of tissue which was contaminated (16 hrs 10 mins) compared with control (11 hrs 10 mins) donors was also significant (p < 10(-6)). We conclude that there is clostridial contamination in a significant number of tissue donors, particularly with increasing time between death and tissue excision. Among the most commonly encountered species is C. sordellii. Multiple microbiological cultures, including blood, are necessary in order to identify clostridial contamination.

Adolescent↗

PubMed2004

The effect of saliva contamination on enamel and dentin using a self-etching adhesive.

BACKGROUND: The authors conducted a study to evaluate the effect of saliva contamination on enamel and dentin before or after application of a self-etching adhesive. METHODS: The authors divided 120 extracted molars into enamel and dentin groups of 60 specimens each, and then further divided each group into three groups of 20 specimens each. Resin-based composite cylinders were bonded to tooth specimens that were uncontaminated (control) or were contaminated with saliva either before or after application of the adhesive and then loaded to the failure point. The authors calculated the mean shear bond strength for each group and subjected data to a one-way analysis of variance, or ANOVA, to test for differences among groups. RESULTS: Mean shear bond strength was 16.7 megapascals (+/- 3.0 standard deviation, or SD) for the dentin control group, 14.8 MPa (+/- 2.3 SD) for dentin contaminated with saliva before adhesive application, 15.9 MPa (+/- 3.8 SD) for dentin contaminated with saliva after adhesive application, 19.1 MPa (+/- 4.8 SD) for the enamel control group, 12.3 MPa (+/- 4.4 SD) for enamel contaminated with saliva before adhesive application, and 13.1 MPa (+/- 5.5 SD) for enamel contaminated with saliva after adhesive application. One-way ANOVA detected no difference in the dentin groups, but the authors found a significant difference among enamel groups. Uncontaminated enamel had higher bond strengths than either of the contaminated enamel groups. CONCLUSIONS: Saliva contamination did not affect the dentin shear bond strength of the self-etching adhesive. Saliva did have a detrimental effect on enamel bond strength. CLINICAL IMPLICATIONS: Newer generations of adhesives appear to be more tolerant of saliva contamination, but proper isolation still should be accomplished until further research proves otherwise.

Acid Etching, Dental↗

PubMedDate not supplied

Plant contamination by organic pollutants in phytoremediation.

Phytoremediation is a remediation technique that involves plant uptake, transformation, accumulation, and/or volatilization of soil- and aqueous-phase contaminants or by the stimulation of microbial cometabolic activity in the rhizosphere of the plant. Even when the principal mechanism is by stimulation of bacteria, any resultant plant contamination cannot be overlooked. For the purpose of modeling, a two-compartment plant model has been developed. The model divides the plant into the shoot compartment (which can be harvested) and the root compartment (into which contaminants can accumulate). Numerical experiments were conducted to investigate model behavior and to determine important parameters affecting plant contamination. Johnsongrass [Sorghum halepense (L.) Pers.] was used to evaluate the model behavior. The contaminants TNT (2,4,6,-trinitrotoluene) and chrysene were selected on the basis of their contrasting aqueous-phase solubilities. The results indicate that plant contamination and soil remediation by plants depend on soil properties such as soil organic carbon content, the physicochemical properties of the contaminants such as the octanol-water partition coefficient, and plant properties. The most important factor affecting plant contamination is bioavailability. As bioavailability increased, the concentrations in root and shoot compartments were predicted to increase. Microbial activities and plant contamination are closely related, which suggests that plants and microorganisms can have complementary roles in phytoremediation.

Biodegradation, Environmental↗

PubMed2002

Effect of latex glove contamination on bond strength.

PURPOSE: This study examined the effect of powdered and powder-free latex glove contamination on bond strength. MATERIALS AND METHODS: Sixty caries-free human third molars were mounted in acrylic, sectioned with a diamond saw to expose a flat occlusal dentin surface, and finished with 400- and 600-grit silicon carbide paper. Teeth were assigned to one of 5 groups: 1) no latex glove contamination (control); 2) powdered latex glove contamination before etching; 3) powder-free latex glove contamination before etching; 4) powdered latex glove contamination after dentin bonding agent application but prior to resin composite placement; 5) powder-free latex glove contamination after dentin bonding agent application but prior to resin composite placement. Excite dentin bonding agent was used per manufacturer's instructions. Z-250 resin composite was applied in 2- x 2-mm increments using a split Teflon mold, each light cured for 20 s. Bonded samples were thermocycled 500 cycles between 5 degrees C and 55 degrees C water baths. Specimens were stored in 37 degrees C distilled water. One-week shear bond strength values were determined using a Tinius Olsen testing machine at a crosshead speed of 0.5 mm/min. Results were analyzed with one-way ANOVA (alpha = 0.05). RESULTS: No significant difference (p = 0.47) in bond strength was found between the experimental groups and the control. Groups 1, 2, 3, and 5 exhibited predominantly mixed failures while the majority of samples in Group 4 showed adhesive failures. CONCLUSION: Under the conditions of this study, contamination of dentin by powdered or powder-free latex gloves did not significantly affect bond strength. Future research should be directed toward evaluating the effects of dentin contamination on bond strength of other bonding agents and include ultrastuctural examination in determining what role, if any, powder plays as a contaminant.

Composite Resins↗

PubMedDate not supplied

Microleakage and penetration ability of resin sealant versus bonding system when applied following contamination.

PURPOSE: The purpose of this study was to evaluate the microleakage and penetration ability of sealing materials applied under different conditions of contamination. METHODS: One hundred twenty extracted human molar teeth were randomly assigned to 12 groups. The treatment groups were defined by the combination of sealing materials (Concise; Optibond system; Optibond system plus Concise) and 4 surface conditions (no moisture and no saliva contamination; moisture contamination; dried saliva contamination; wet saliva contamination). Each tooth was subjected to thermal cycling (5,000 cycles at 5 degrees C-55 degrees C) with a dwell time of 30 seconds and dye immersion (5% methylene blue for 24 hours). Microleakage, penetration ability, and fissure types were examined after sectioning. Multiple regression analyses and the Tukey test were used for statistical analysis. RESULTS: Concise showed significantly less microleakage than the Optibond system (P<.031) when the procedures were performed under no contamination or moisture contamination. However, when Concise was applied on the wet saliva-contaminated surfaces, considerably higher microleakage and unfilled areas were found compared to the use of Optibond alone or Optibond with Concise (P<.001). CONCLUSIONS: When there is saliva contamination, the use of Optibond alone or with Concise is beneficial for decreasing microleakage and increasing the penetration ability of sealants.

Bisphenol A-Glycidyl Methacrylate↗

PubMed1985

[Growth rates of two virulence plasmids carrying Yersinia enterocolitica after contamination of heated milk, raw minced pork and vegetables].

The psychrotrophic organism Y. enterocolitica (Y.e.) is able to grow in foodstuffs thus rendering it dangerous for the consumer. Among others, the preparation of food in the kitchen might be an important way of transmission. Not only contaminated raw meat but aswell latently infected humans and pet animals (cats, dogs) may serve as a reservoir for Y.e. contamination. After artificial contamination of UHT milk and vanilla sauce with subsequent storage at 4 degrees C, two Y.e. strains of serovars 0:3 and 0:9 carrying the virulence plasmid multiplied during the first 6 d (9 d) at a rate of 1 log/d (Fig. 1). In pasteurized milk the multiplication rate was 0,65 log/d (Fig.2). Maximum bacterial counts in UHT milk after 15 d were in the order of 10(9) CFU/ml (Fig.4). In pasteurized milk, even minimal inoculation doses of less than 5 CFU/100ml (calculated) produced multiplication of Y.e. to 1,7-27 X 10(4) CFU/ml after 7 d (Tab.1). In this case the milk has been contaminated by an appropriately diluted suspension of faeces from infected mice. When selected colonies were tested on MOX-Agar, a loss of the virulence plasmid could not be observed. In minced fresh pork meat with a bacterial count of 4,2 X 10(6) CFU/g--most of them i.e. 2,6 X 10(6) belonging to Pseudomonas sp.--added Y.e. did not multiply, but viable organisms could be recovered after contamination with only 2,9-6,6 X 10(2) CFU Y.e./g and storage at 4 degrees C for 72 h (Tab.2). Similarly, after contamination of quartered paprika husks and halves of carrots, Y.e. strains could be re-isolated after 15 d storage at 4 degrees C or room temperature if the number of bacteria used for inoculation was in the range of 10(6) (Tab.3). Feeding contaminated carrots to NMRI-mice a calculated number of 5 X 10(3) CFU Y.e./mouse were sufficient to cause infection of part of the animals together with shedding of the organisms through the faeces (Tab.4). These results support the assumption that milk and home made milk products like vanilla sauce create a risk for human health when they are stored for a few days after contamination with Y.e. carrying the virulence plasmid. The same may be true for raw minced pork and fresh vegetables but only if the initial contamination was high. This might occur during food processing procedures.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1980

[Bacterial contamination as a complication of intravenous therapy in intensive care (author's transl)].

Intravenous infusion therapy has become an indispensible part of intensive care. Problems of bacterial contamination during this therapy are well known. To check on the possible routes of contamination we examined the infusion system in its several parts (infusion solution, infusion system, connection between infusion system and catheter and content of syringes). The highest rate of contamination was found at the connection between the infusion system and the catheter after use for 24 h (26.7%, 39 out of 146 probes); just at the beginning of the infusion we found bacterial growth in 7.1% (10 out of 141 probes). After injection of drugs into the system the infusion solution was contaminated in 1.9% (6 of 320 probes). The system for measuring the central venous pressure was contaminated in 2.7% (4 of 148 probes). At the end of infusion the infusion solutions were contaminated in 3.1% (9 of 287 probes). Different drugs in syringes in no case were contaminated. In most cases (59 probes) we found gram-positive bacteria (87.3%), in only seven cases (9.7%) gram-negative bacterias and in two cases Candida tropicalis. Our results show that the extrinsic or in use contamination plays the most important part in bacterial contamination of the infusion system. Infection control of intravenous therapy necessitates care in the hygienic standard adopted during the infusion and injection procedures.

Antisepsis↗

PubMed2002

Assessment and development of procedures and apparatus to reduce contamination of lamb carcasses during pelt removal in low-throughput abattoirs.

Two series of experiments were carried out to investigate methods of reducing contamination of lamb carcasses in low-throughput abattoirs, where cradle dressing is normally employed. In the first series, cradle design and pelt removal procedure were investigated, and a method was developed for assessing gross visible contamination. Significant improvements in microbiological and gross visible contamination (P < 0.01) were achieved by procedural changes only; modifications to the cradle design had no effect. In the second series of experiments, two improved methods of pelt removal and the effect of hand washing prior to carcass contact during the pelt removal procedure were investigated. The improved methods comprised a Frame system, in which the pelt was removed in a manner similar to that in a high-throughput inverted line, and a Hybrid system, in which the pelt was removed from the forequarters on a conventional cradle before the carcass was suspended in an "inverted" vertical position for removal of the pelt from the abdomen and hindquarters. The results of microbiological and gross visible contamination from these methods, with and without hand washing, were compared with the conventional Cradle method of pelt removal. Both the Hybrid and Frame systems had significantly less microbiological and gross visible contamination (P < 0.01). However, hand washing had no significant effect on the level of carcass contamination for all three methods of pelt removal. Greatest reductions in microbiological and gross visible contamination were achieved using techniques that minimized hand contact with the carcass during pelt removal by adoption of inverted dressing procedures. Equipment redesign did not reduce carcass contamination.

Abattoirs↗

PubMed1995

Bacterial contamination of aerosol solutions containing antibiotics.

In an investigation of microbial contamination of aerosol solutions containing antibiotics (hospital pharmaceutical preparations, no preservatives added), five of six residual solutions after multiple use for 7 days were contaminated at a concentration of 10(6) viable counts/ml. Contaminants were glucose-nonfermenting Gram-negative bacilli such as Pseudomonas cepacia and Flavobacterium meningosepticum. The major contaminant, P. cepacia, multiplied rapidly in the aerosol solution under simulated actual-use conditions. The contamination seemed to have been caused by storage, at room temperature instead of in a refrigerator, of the multiple-dose solutions and by frequent re-use of syringes to measure the solutions. Prompt refrigerator storage after each use of the solutions and abandonment of the syringes within 24 h eliminated bacterial contamination of the solutions. Sufficient attention is not paid to prevent bacterial contamination of aerosol solutions containing antibiotics because of the fact that they contain antibiotics. Thus aerosol solutions containing antibiotics should be handled with great care to prevent bacterial contamination.

Aerosols↗

PubMed1995

Effectiveness of cleaning surgical implants: quantitative analysis of contaminant removal.

Surgical implants need to be free from contaminants before implantation. The effectiveness of a presently used Clemson bioengineering cleaning (CBC) protocol was evaluated for cleaning three different biomaterials (titanium, aluminum oxide, and polyethylene terephthalate, PET) contaminated with three different contaminants (calcium chloride, zinc chloride, and hexadecane). Radiolabeled tracer analysis (RTA), with the use of liquid scintillation, was used as the surface analytical technique to quantitatively determine the percent contaminant removed from the biomaterial surface. On average, the ultrasonic cleaning step removed 99.96% of all three contaminants from both titanium and aluminum oxide. The CBC protocol did not sufficiently clean PET fabric contaminated with hexadecane leaving 11.76% of the contaminant after the ultrasonic step. With the use of isopropyl alcohol in series with 1% Liquinox, the ultrasonic step cleaned the fabric soiled with hexadecane within 30 min, removing 99.85% of the hexadecane initially on the surface. RTA proved to be an excellent method of quantifying surface contamination on implant materials, and for assessing the effectiveness of cleaning protocols in question.

Alkanes↗

PubMedDate not supplied

Risk assessment and management of chemical contaminants in fishery products consumed in the USA.

In the USA a small proportion of fishery products are contaminated with appreciable amounts of potentially hazardous contaminants. However, risks to consumers are not generally high. Inorganic contaminants with the greatest potential for toxicity are antimony, arsenic, cadmium, lead, mercury, selenium and sulfites. Among organic compounds, polychlorinated biphenyls, dioxins, several chlorinated hydrocarbon insecticides, certain processing-related and aquaculture-related contaminants pose potential risks for consumers. Log-normal distributions appear to provide good descriptions of the pattern of variation of contaminant concentrations among different geographic areas, and some contaminants (mostly organic) appear to be much more variable than others. This variability offers a solution for reduction of exposure through restricting the harvest of aquatic organisms from specific sites, and by excluding certain species. It is recommended that: (i) existing State and Federal regulations and environmental monitoring be strengthened and enforced to minimize contamination of the aquatic environment; (ii) a program of shared responsibility be instituted, where Federal agencies develop a set of monitoring and inspection practices and state agencies assume responsibility for primary control, site closures and advisories issue; (iii) research and public education by government agencies and health professionals be expanded to determine actual risks and approaches to manage them; (iv) mandatory labeling be considered for specific contaminants; (v) a better system requiring international agreements be developed in order to minimize the differences among various national regulatory approaches.

Animals↗

PubMed2006

A novel approach for in-process monitoring and managing cross-contamination in a high-throughput high-performance liquid chromatography assay with tandem mass spectrometric detection.

Cross-contamination among wells of a high-throughput, high-density assay is a risk that cannot be detected or controlled by the performance of calibration standards and quality control samples. In the current practice, carryover and cross-contamination is detected only when analytes are detected in blank, zero, placebo, pre-dose samples, in a low standard or low quality control sample. There is no mechanism that allows bioanalytical scientists to determine if cross-contamination has occurred among other samples. As a result, erroneous results can be released to clients even though a batch meets the acceptance criteria. We tested a new approach that quantifies the cross-contamination of each sample and allows the scientist to make quality decisions with documentation. The approach will also detect carryover in over 90% of the wells. Briefly, two additional analytes were added as contamination markers. The markers were added to a multi-well plate alternatively creating a pattern of a checkerboard. The spiked multi-well plate was then used to perform the assay. If both markers were detected in a well, the sample was considered contaminated. The amount of the unexpected marker detected in a well measures the degree of contamination and may be used to make deactivation decisions. Depending on the relative impact of the contamination, a scientist can choose to tolerate the bias, reject the sample, reject the batch or raise the lower limit of quantitation for the batch. A guideline for rejection decisions is presented for discussion.

Biomarkers↗

PubMed2001

Dioxin contamination in food. Bayreuth, Germany, from September 28 to October 1, 2000.

Dioxin and PCB monitoring programs for food and feeding stuff in most countries of the world, including many European Countries are currently inadequate. Better control of food production lines and food processing procedures is needed to minimize entry of dioxin to the food chain and will help to avoid dioxin contamination accidents. This would also improve the ability to trace back a possible contamination to its source. European guidelines for monitoring programs should be established to ensure comparable and meaningful results. These guidelines should define the minimum requirements for the design of monitoring programs, analytical methods, and quality assurance. Though data from Northern Europe shows that the general population exposure to dioxin and PCB has decreased during the last ten years these compounds continue to be a risk of accidental contamination of the food chain. The most prominent recent example is the Belgian dioxin contamination of feeding stuff in 1999. The Belgian dioxin contamination was not detected due to dioxin monitoring programs but by their direct biological effects seen in animals. Four other cases of dioxin contamination have been detected in Europe since 1997 due to local monitoring programs. One of them (citrus pulp pellets 1998) was in a much larger scale than the Belgian dioxin contamination. The general population's exposure to dioxins and PCBs is still in the same range (1-4 pg WHO-TEQ/kg body weight and day) as the recently revised WHO tolerable daily intake (TDI). There is concern that short-term high level exposure to dioxins, furans, and PCB may cause biological effects on the human fetal development and further research is required. Further actions to control sources building on considerable advances already made in many countries may need to be supplemented by measures to prevent direct contamination of feeding stuff or food to reduce general population exposure further.

Animal Feed↗