Rinse Method Research Articles

The reduction of toxic metals of various rice types by different preparation and cooking processes – Human health risk assessment in Tehran households, Iran

In this study, the effect of washing, soaking (1, 5 and 12 h), and cooking rice methods including Rinsed (boiling in excess water) and Kateh (conventional) cooking on the reduction of the arsenic (As), lead (Pb), and cadmium (Cd) were evaluated. The results showed that the rinsed cooking has higher efficiency for removal of toxic metals (As = 42.3%, Pb = 42.9% and = 27.6%) than Kateh method (As = 26.9%, Pb = 26.9% and = 20.9%). Additionally, by increasing of rice soaking time from 1 to 12 h, the toxic metals removal was increased up to 37.1%, 42.6% and 16.6% for As, Pb and Cd, respectively. Although the toxic metals reduction was such that the non-carcinogenic risk was regarded as acceptable level after all processes, for arsenic, these reductions did not lower the carcinogenic risk to an acceptable level. Finally, it is suggested that Tehran households, after washing and soaking to 5 h, then cook it by rinse method.

A method for improved fluorescent staining for acid fast smear microscopy by incorporating an acetone rinse step

Microscopic examination of the specimen smear for acid fast bacilli (AFB) provides a simple and rapid means of detecting AFB using fluorescent stain methods and remains a valuable diagnostic test used worldwide to identify and manage suspect cases of tuberculosis (TB). Methods to improve AFB smear staining protocols could provide better detection of suspect TB cases. In particular, decreasing background debris may improve the detection of smears with low numbers of bacilli. We assessed staining by the standard rack method compared to bulk container staining using an acetone rinse step to decrease background debris. No cross-contamination was observed in the bulk container staining, and higher accuracy with less reading time was achieved with the acetone rinse. Most importantly, more bacilli were detected per positive smear using the acetone rinse method.

Molecular epidemiology of human papillomavirus genotypes in oral rinses from HIV-positive and HIV-negative Jamaican patients.

Human papillomavirus (HPV) has been reported to be associated with oral and oropharyngeal cancer. However, little information is available about the epidemiology of oral HPV infection in Jamaica. The purpose of the present study was to assess the prevalence of oral HPV strains using the oral rinse method in HIV and non-HIV Jamaican patients, as well as to determine the association of HPV with sexual practices, smoking, and alcohol use. A cross-sectional study was conducted on patients attending The University of the West Indies Mona Dental Polyclinic and the Centre for HIV/AIDS Research and Education Services. Salivary samples were tested through molecular analysis for 37 HPV genotypes using the linear array HPV genotyping test. A survey questionnaire was used to obtain demographic details, smoking history, alcohol practice, sexual practice, and history of HPV testing. The HPV prevalence was 8.65% in 18-64y olds (N=104), with a slight female predilection (55%). No high-risk HPV types were found. HPV-84 was the most common type in both HIV and non-HIV patients; 66.7% of HPV-positive participants reported that they had six or more lifetime sexual partners. The prevalence of oral HPV was similar to that in other countries. No statistically-significant relationship was observed between the prevalence of HPV and either the number of sexual partners, smoking, or alcohol history. A nationwide study on oral HPV detection might be helpful in developing a HPV vaccination policy in Jamaica.

Neutralization of residual antimicrobial processing chemicals in broiler carcass rinse for improved detection of Campylobacter

The USDA-Food Safety and Inspection Service (FSIS) has established pathogen reduction performance standards for Campylobacter on broiler carcasses. Processors may apply antimicrobial processing aids as a spray or immersion to lower contamination on carcasses. In the United States, broiler carcasses are generally sampled by whole carcass rinse and the potential exists for residual levels of antimicrobial processing aid to be carried over into the rinsate. It has been shown that, if un-mitigated, such carryover can interfere with the detection of Salmonella. In the current study, we demonstrate that unmitigated carryover of antimicrobial treatment also can interfere with the detection and recovery of Campylobacter in broiler carcass rinse samples. We tested traditional buffered peptone water and found that it did not offer enough neutralizing capability to counteract residual antimicrobial activity of some post-chill processing aids (peroxyacetic acid, cetylpyridinium chloride, acidified sodium chloride, or a blend of acids) to allow full recovery of Campylobacter. A recently reported formulation for a neutralizing buffered peptone water (currently being used by FSIS) outperformed the traditional carcass rinse medium and allowed significantly improved recovery of Campylobacter even in the presence of 3 of the 4 tested antimicrobial processing aids. Performance of the new carcass rinse medium with the fourth antimicrobial processing aid (acidified sodium chloride) was not different from the traditional formulation. Neutralizing buffered peptone water represents a significant improvement in the broiler carcass rinse method for detection of Campylobacter.

Prevalence and serotypes of Salmonella spp. on chickens sold at retail outlets in Trinidad.

BackgroundThis cross-sectional study determined the prevalence of Salmonella spp. and their serotypes on dressed chicken sold at retail outlets in Trinidad. The study also investigated the risk factors for contamination of dressed carcasses by Salmonella spp. at cottage poultry processor outlets where chickens are slaughtered and processed for sale.MethodsA total of 133 dressed, whole chickens and 87 chicken parts from 44 cottage poultry processors and 36 dressed, whole chickens and 194 chicken parts from 46 supermarket outlets were randomly collected throughout the country. Isolation and identification of Salmonella spp. were performed using standard bacteriological techniques. Serotyping was performed by a regional reference laboratory.ResultsThe prevalence of Salmonella spp. in chicken carcasses sampled from cottage poultry processors and supermarkets was 20.5% and 8.3% respectively (p <0.001). The frequency of isolation of Salmonella spp. at cottage poultry processors was 22.4%, 23.0%, 7.1%, and 10.0% for non-chilled whole chicken, non-chilled chicken parts, chilled whole chicken and chilled chicken parts respectively. Fresh, non-chilled chicken (22.6%) yielded a higher frequency of isolation of Salmonella spp. than chilled chickens (8.3%). For supermarket samples, the frequency of isolation of Salmonella spp. was 19.0%, 8.1%, 0.0% and 7.6% for chilled whole chickens, chill chicken parts, frozen whole chicken and frozen chicken parts respectively. The swab method of sampling yielded a statistically significantly (p = 0.029) higher frequency (3.2%) of Salmonella spp. than the rinse method (1.6%). The predominant serotypes isolated were Kentucky (30.9%) and Javiana (22.7%). Use of chilled water-bath to cool carcasses was the only risk factor significantly (p = 0.044) associated with isolation of Salmonella spp.ConclusionRaw chicken carcasses purchased from cottage poultry processors pose a significantly higher risk of contamination with Salmonella spp. than those sold at supermarkets.

CFD modelling of axial mixing in the intermediate and final rinses of cleaning-in-place procedures of straight pipes

The intermediate and final rinses of straight pipes, in which water replaces a cleaning agent of similar density and viscosity, are modelled using Computational Fluid Dynamic (CFD) methods. It is anticipated that the displacement process is achieved by convective and diffusive transport. The simulated agent concentrations show good agreement with the analytical axial mixing models from literature. The displacement time, minimum water consumption, minimum generation of wastewater and minimum requirement of intermediate rinsing water are evaluated using CFD. Practical empirical equations are derived from CFD results and applied to examine if the process is operated in an efficient and economic manner. It has been found that the displacement time can be predicted from the inner pipe diameter and the mean flow velocity using a power law relationship. Changing flow velocities does not significantly influence the minimum water consumption and the minimum wastewater generation for rinsing a pipe. Controlling the rinsing step based on a downstream measurement still consumes more water than the minimum requirement to reduce contamination risks. This article presents an innovative algorithm for optimizing the rinse steps with lower water consumption based on the above observations. A case of rinsing a 24 m long straight pipe describes the promising application of the CFD study. The recovery of cleaning agent can be up to 89.3% of the volume and the saving of intermediate rinsing water can be at least 55% compared to the conventional rinse method. The work in this article presents an example showing how to deal with more complex systems in the future.

Pre-scald brushing for removal of solids and associated broiler carcass bacterial contamination

The aim of the study was to investigate the effect of brushing prior to scalding on reducing the E. coli and Enterobacteriaceae concentrations on carcasses. Three visits were arranged to a commercial slaughterhouse in which carcasses were cleaned in a separate line. Ten batches were sampled to compare the E. coli and Enterobacteriaceae concentrations on carcasses before and after a stand-alone brushing unit. Per batch, 8 carcasses before and 8 after brushing were sampled by the whole-carcass rinse method. Furthermore, the dry matter content and the pH were determined in these samples, as these parameters indirectly (dry matter) or directly (pH) influence the scalding lethality. Results revealed a small but statistically significant reduction (P < 0.001) in E. coli and Enterobacteriaceae concentrations on the brushed carcasses. The concentrations on whole carcasses were reduced on average by 0.3 log for both E. coli and Enterobacteriaceae. Rinse samples from treated carcasses had significantly less dry matter on average by 2.5 g (P < 0.001) and significantly higher pH by 0.08 units (P < 0.001). Although these differences are statistically significant, they might have rather low biological relevance; thus, further optimization of brushes is needed for more relevant results. This study confirms that brushing reduces bacterial concentrations on carcasses, which may be increased potentially by enlarging the brushed surface of the carcass. Further in-line investigations are needed to observe the effect of brushing on bacterial concentrations in scalding water and on carcasses after scalding and at the end of processing.

A new approach to exfoliative cytology: A comparative cytomorphometric study.

Early detection of oral premalignancy and malignancy using simple screening aids play a promising role in curbing the disease. The primary aim of this study is to evaluate and the secondary aim of this study is to compare the cytomorphometry and cellular atypia in keratinocytes obtained from oral rinse and conventional exfoliative cytology in normal oral mucosa and clinically diagnosed oral leukoplakia. The study comprised of 55 clinically diagnosed cases of leukoplakia and 55 age and sex matched normal controls. Smears were prepared using oral rinse technique followed by the conventional exfoliative cytology. Papanicoloau stained smears were evaluated for atypia and subjected to image analysis. Based on the presence of atypia they were further divided into three groups (Group 1-cases with atypia, Group 2-without atypia and Group 3-normal controls) and analyzed. Statistical analysis used one-way analysis of variance followed by Tukey Honestly Significant Difference test for intergroup analysis and unpaired students t-test to compare the two methods. Smears prepared with both methods demonstrated atypia in 18 cases. The cellular diameter and cellular area (CA) were progressively increased from Group 1 through Groups 2 and 3 in both the smears. Nuclear diameter and nuclear area and nuclear cytoplasmic ratio progressively decreased from Group 1 through Groups 2 and 3. Both the methods showed no significant differences among the cellular parameters except in normal controls. Cytomorphometric analysis of keratinocytes obtained with oral rinse method and wooden spatula can serve as a useful screening aid to detect oral leukoplakia. Oral rinse method being more convenient results in smears of better quality.

Candida concentrations determined following concentrated oral rinse culture reflect clinical oral signs.

BackgroundOral candidiasis is an infection caused by a yeast-like fungus called Candida. Various methods can be used to isolate Candida from the oral cavity. However, it is difficult to correctly and satisfactorily diagnose oral candidiasis because currently no microbiological or laboratory standards based on samples from the oral cavity are available. The aim of this study is to establish a reliable laboratory test for diagnosing oral candidiasis.MethodsOral swab, rinse and concentrated rinse samples were obtained from 200 consecutive outpatients (103 male patients and 97 female patients; mean age, 47.2 years; age range, 9–89 years). Candida colonies from cultured samples were enumerated to compare the sensitivities and specificities of the above sampling methods, and the associations between Candida detection or concentration and the clinical oral signs were examined.ResultsThe mean colony numbers were 263 ± 590 CFU/swab for the swab method, 2894 ± 6705 CFU/100 μL for the rinse method, and 9245 ± 19,030 CFU/100 μL for the concentrated rinse method. The median numbers were 23 CFU/swab for the swab method, 56 CFU/100 μL for the rinse method, and 485 CFU/100 μL for the concentrated rinse method. Candida was detected in the oral cavity of 33.5 % and 52.0 % of the outpatients by the swab method and concentrated rinse, respectively. Candida concentrations determined by the concentrated rinse were closely related to the severity of the clinical oral signs. The positive predictive values of residual root, redness of the oral mucosa, denture, glossalgia, dry mouth, and taste disorder were useful predictors of oral candidiasis.ConclusionsConcentrated rinse sampling is suitable for evaluating oral candidiasis, and Candida concentrations examined using this method strongly associated with the oral signs associated with Candida infection.

Agreement of 3 carcass rinse sampling methods (split carcass, repeat rinse, and adjacent pair) on the detection of Salmonella contamination in broiler carcasses

Whole carcass rinse is the most common method used to determine Salmonella prevalence in broiler carcasses. However, there is a need to determine the carcass rinse sampling method that best measures the Salmonella status of a broiler carcass as it proceeds through processing, thus allowing the assessment of efficacy of interventions to meet Food Safety Inspection Services (FSIS) performance standards.In this study, 3 paired carcass rinse sampling methods, namely split-carcass method (rinses of 2 halves of one carcass), repeat rinse method (rinse and rerinse of same carcass), and adjacent pair method (rinses of 2 adjacent carcasses), were evaluated during actual operations in commercial poultry processing plants in the southeastern United States. The purpose of the work was to determine which method resulted in greatest agreement of Salmonella status on paired broiler carcass rinses.The adjacent pair method showed moderate agreement consistently in 3 trials of 150 pairs per trial with kappa values of 0.46, 0.55, and 0.46. The repeat rinse method showed substantial kappa agreement (0.64) in one trial and moderate kappa agreement (0.47, 0.41) in 2 other trials. In one trial, the repeat rinse method showed a significant difference in prevalence rates between repeated rinses. Even though the split carcass method showed moderate kappa agreement (0.58, 0.45) in 150 carcasses in each of 2 trials, the disadvantages of the split carcass method were that it was more labor and time intensive and the product was damaged, when compared to the other 2 methods. Overall, although prevalence estimates were fairly consistent between pairs by each method, agreement between Salmonella status of the paired samples was less than desired, mostly moderate. This lack of agreement should be considered in the design of studies assessing the efficacy of interventions for the control of Salmonella in broilers to meet FSIS performance standards.

PCB기판 세척용 스핀 지그개발에 관한 연구

본 연구는 PCB기판 세척에 관한 것으로 기존 세척 방법인 침전식 세척의 단점인 PCB기판 표면실링제와 접착제 공정에서 형성된 이물질이 달라붙거나 끼워 있는 경우, 쉽게 제거되지 못하는 문제점이 있었다. PCB기판이 안착되어 고속회전을 통해 원심력으로 기판의 미세한 부분까지 이물질이 제거되도록 하는 PCB기판 세청용 회전 지그를 개발 하였다. 결과는 다음과 같다. 개발 목표는 PCB기판 세척시 불량률을 줄이는 것으로 기존 침전식에서, 원심력을 이용한 회전형으로 개발, 세척액에 따른 기판손상을 80%이상 줄이는 결과를 얻었다. 회전식에 따른 세척할 수 있는 수량이 제한된 단점을 베이스플레이트에서 PCB기판의 용이한 탈부착이 가능하도록 설계 기존 방법의 세척 후 공정을 포함한 시간과 비교하여 큰 차이를 보이지 않았으며. 기존 시간과 비교하여 세척시간을 90%까지 높였다. 세척용 회전 지그에 고정된 PCB기판이 원심력에 의해 이탈현상 없이 고정력을 효과적으로 유지 할 수 있도록 설계함으로써, 세척공정의 안정성 및 신뢰성을 확보하여 불량률을 1% 미만으로 개선 할 수 있었다. This study examined PCB component cleaning on a PCB component surface, which has defects of precipitation type washing (existing rinse method), sealant and foreign material formed in the adhesive process that could not be removed easily. The spin jig was developed for PCB component cleaning, in which the PCB component settled down, to solve the conventional problem of the removal of foreign material with the centrifugal force by high speed rotation. The results are as follows. With decreasing fraction defect in PCB component washing, the development and substrate damage decreased by more than 80% according to the abstergent in the rotary type using the centrifugal force in the existing precipitation type. When the base plate showed a large difference with the time to include the process after washing the design using the existing method, easy attachment and separation of the PCB component could be possible. The washing time was enhanced 90% compared to the existing time. The reliability of the security and washing collaboration of the design and stability of the cleaning process could be secured so that there was no phenomenon of secession, the PCB component fixed for a cleansing rotation jig could maintain a fixed force by the centrifugal force. The stability and reliability of the washing process and the defective rate could be improved to less than 1%.

Foliar rinse study of atmospheric black carbon deposition to leaves of konara oak (Quercus serrata) stands

Dry deposition of Black Carbon (BC) to the actual leaves of konara oak (Quercus serrata) was evaluated in a foliar rinse method in an experimental forest in the suburbs of Tokyo, Japan in order to explore deposition levels and vertical profile within the forest. At three heights of the forest of 20 m height, 20 m, 15 m, and 6 m or 4 m, leaves were sampled on a weekly basis for a couple of months in 2011 and 2012 and subjected to rinsing with water and chloroform. The BC in the rinse solution was collected on a quartz fiber filter and determined by spectrophotometry. The BC mass deposited to leaves increased with height and this profile pattern was generally maintained in the study period. The specific BC mass deposited to leaves showed considerable fluctuations with time, but the deposited BC increased rapidly with time in the bud flushing stage, then attained to a plateau, and began to decrease as the defoliation advanced. The plateau is a result of a simple accumulation with time and occasional removal due to rainfall and strong winds. The maximum BC mass deposited to leaves per leaf surface unit area occurred in June where the level was 10–15 mg-BC m−2. The rate of BC mass deposited to leaves at the time of leaves growing was determined to be 0.237 and 0.277 mg-BC m−2 day−1 for measurements in 2011 and 2012, respectively. On the basis of the observed BC mass deposited to the leaves, BC mass deposited to leaves per forest floor unit area estimated with LAI showed a strong seasonality. The BC mass deposited to leaves per forest floor unit area was compared to the deposition flux from the atmosphere to the forest canopy, which would be interpreted as indicating that 30% of atmospheric BC deposition to the canopy was retained on the leaves in time of leaves growing.

Cytomorphological analysis in oral squamous cell carcinoma lesions and normal controls using rub and rinse technique

Context: Early diagnosis of oral cancer requires simple noninvasive screening tools. Aim: To analyze the cytomorphological features of keratinocytes in smears obtained from the oral mucosa of oral squamous cell carcinoma (OSCC) lesions and normal controls using oral rub and rinse technique. Settings and Design: Oral smears were prepared using oral rub and rinse method in subjects with OSCC cases (n = 35) and apparently healthy normal controls (n = 35). They were subjected to cytomorphometric analysis. Materials and Methods : The smears prepared with the rinse method were stained with Papanicolaou stain. Quantitative assessment of nuclear diameter (ND), cytoplasmic diameter (CD), cellular area (CA), nuclear area (NA), and nuclear cytoplasmic ratio (N:C) was carried out. Statistical Analysis Used: Unpaired Student's t-test was used to compare the mean value between the groups. Results: There was a significant difference between ND, CD, CA, NA, and N: C of oral cancer cells and that of the normal controls. There was increase in the mean ND, NA, and N: C; and decrease in CA and CD of cancer subjects when compared to that of normal controls. Conclusion: Cytomorphometric analysis of keratinocytes obtained with oral rinse method can serve as a useful adjunct in the early diagnosis of OSCCs.

Detection of species diversity in oral candida colonization and anti-fungal susceptibility among non-oral habit adult diabetic patients

Background and Objectives:Patients with diabetes mellitus are prone to secondary infections. In this study we aim to determine the prevalence of one such secondary infection (oral Candida colonization) and evaluate the influence of local and systemic factors on the oral candidal colonization in patients with diabetes mellitus.Materials and Methods:Forty non-insulin-dependent diabetic patients and 40 healthy individuals were included in this study. Samples were collected by using the oral rinse method. The candidal species were isolated and identified through phenotypic methods. An in vitro antifungal susceptibility profile was evaluated. Glycemic control, as determined by the glycosylated hemoglobin concentrations (HbA1c) of the study subjects, was correlated with the candidal colonization.Results:Patients with diabetes showed a significantly higher prevalence of candidal colonization. The rate of carriage and density (P = 0.001) was higher. Candida albicans was the most predominantly isolated species, however, C. dubliniensis, C. tropicalis, and C. parapsilosis were also observed. Variable resistance toward the antifungal drugs (amphotericin B and fluconazole) was observed in the Candida isolated from diabetics, but not from healthy patients. Interestingly, a positive correlation was observed between glycemic control and candidal colonization.Conclusion:Diabetic patients had a higher candidal carriage rate, with a variety of candidal strains, which significantly varied in their resistance to routinely used anti-fungal agents. Interestingly the higher oral candidal colonization in diabetic patients is related to local and systemic factors, independent of their oral habits.

Isolation of DNA from oral rinse in HPV positive patients.

To extract human genomic DNA from oral rinse in HPV positive patients. Experimental study. Research Laboratory, Ziauddin Medical University, from February to July 2011. Two hundred and fifty oral rinse samples from human papilloma virus (HPV) positive subjects were collected in 50 ml corning tubes. DNA was extracted from 10 ml of oral rinse by using Lysis buffer (sodium dodecyl sulfate, sodium chloride, sodium citrate and EDTA), isopropanol and 3 M sodium acetate and final washing with ethanol. The DNA was quantified by using Qubit dsDNA BR Assay (Qubit 2.0 invitrogen life technologies USA) and the quality was checked by running an aliquot on 0.6% agarose gel stained with ethidium bromide. PCR were done to amplify b-globin gene on chromosome11 by using primers GH20/PCO4 of 260 bp fragment. The mean concentration of all 250 samples DNA was 15.648 ± 10.50 μg/ml determined by using Qubit 2.0. A single intense band without smearing was seen in almost all cases which confirmed the integrity of DNA. The PCR amplification of human b-globins primers was successfully done. The oral rinse method was found a simple and highly appropriate means for non-invasive sample collection with easy storage, DNA recovery and subsequent PCR amplification in HPV positive patients.

Preliminary Determination of the Microbial Count on X-Ray Tables in Selected Hospitals in Cagayan de Oro City, Philippines

This study aimed to determine the microbial count present on x-ray tables utilized during x-ray examinations with patients in Radiology Departments of Cagayan de Oro City hospitals. Particularly, it sought to evaluate and assess the sanitary conditions of these x-ray tables. This study used the evaluation research approach to determine the sanitary level of the x-ray tables. In order to rate the sanitary level, “Collins and Lyne’s Microbiological Method Chapter 17 – Swab” was used as the guide of the study. This method made use of the swab rinse method. The parameter utilized the total plate count which was an estimation of the number of viable cells in a culture. Based on the microbial count results released by DOST, Hospitals A, B, and C yielded microbial counts of 28, 40, and 36 CFU/ cm² respectively while Hospitals D and E yielded 100 and 164 CFU/cm² respectively. Based on the findings, Hospitals A, B, and C yielded microbial counts that were less than 100 CFU/ cm² and are within the limits established by USPHS, thus, they were considered sanitary. Meanwhile, Hospitals D and E have exceeded the limits and were considered unsanitary. KEYWORD - Microbial count, Total Plate Count, X-ray Tables, Collins and Lynne’s Microbiological Method, Aseptic Technique in Radiology Department, Swab Rinse Method.

An assessment of geochemical preparation methods prior to organic carbon concentration and carbon isotope ratio analyses of fine‐grained sedimentary rocks

This study summarizes organic carbon isotope (δ13C) and total organic carbon (TOC) data from a series of tests undertaken to provide an appropriate methodology for pre‐analysis treatment of mudstones from an Upper Carboniferous sedimentary succession, in order to develop a consistent preparation procedure. The main treatments involved removing both inorganic carbonate and hydrocarbons (which might be extraneous) before δ13C and TOC analysis. The results show that decarbonating using hydrochloric acid causes significant reduction in δ13C and total carbon (TC) of the bulk material due to the removal of inorganic carbonate. These changes are most pronounced where soluble calcium carbonate (rather than Ca‐Mg‐Fe carbonate) is present. Deoiled samples show only slightly higher mean δ13C where visible bitumen was extracted from the bulk sample. Moreover, the isotopic signatures of the extracts are closely correlated to those of their respective bulk samples, suggesting that small yields of hydrocarbons were generated in situ with no isotopic fractionation. In addition, further δ13C and TC analyses were performed on samples where mixing of oil‐based drilling mud with brecciated core material had been undertaken. Brecciated mudstone material did not display distinct isotopic signals compared to the surrounding fine‐grained material. Overall we show that the most accurate assessment of bulk organic carbon isotopes and concentration in these samples can be achieved through decarbonating the material prior to measurement via the ‘rinse method’. However, our results support recent findings that pre‐analysis acid treatments can cause variable and unpredictable errors in δ13C and TOC values. We believe that, despite these uncertainties, the findings presented here can be applied to paleoenvironmental studies on organic matter contained within sedimentary rocks over a range of geological ages and compositions.

Prevalence of Salmonella on retail chicken meat in Russian Federation.

The objective of this study was to estimate the prevalence of Salmonella on raw retail chicken meat in Russia. Broiler chicken carcasses (n = 698) were collected from three regions of Russia: central (i.e., Moscow area), northwest (i.e., St. Petersburg area), and southern (i.e., Krasnodar area). In each region, samples were collected to represent various cities and districts, as well as different types of retail stores and carcass storage temperatures (i.e., chilled and frozen). All chicken samples were analyzed for the presence of Salmonella using a whole-carcass rinse method. The overall Salmonella prevalence was 31.5%. There were significant differences (P < 0.05) in Salmonella prevalence by (i) region-29.3% (n = 464) in Moscow, 38.5% (n = 192) in St. Petersburg, and 23.8% (n = 42) in Krasnodar; (ii) retail store type-28.8% (n = 236) in hypermarkets, 31.9% (n = 260) in supermarkets (part of chain stores), 44.3% (n = 61) in independent supermarkets, 42.9% (n = 28) in independent minimarkets, and 26.6% (n = 113) in wet markets; and (iii) poultry company-34.3% (n = 545) on chickens produced by integrated companies compared with 22.9% (n = 118) on chickens produced by nonintegrated companies. Strategies such as good agriculture and management practices should be enhanced to reduce Salmonella prevalence on raw poultry in Russia and therefore increase the safety of chicken products.

Laboratory evaluation of large-scale decontamination approaches

To evaluate the effectiveness of two spray-based decontamination methods for surface contamination reduction and to determine the potential for contamination spread by these methods. Material coupons (treated plywood and concrete) were contaminated with c. 1 × 10(7) spores of Bacillus atrophaeus by aerosol deposition. Decontaminants (pH-adjusted bleach or Spor-Klenz(®) RTU) were applied to coupons by either backpack sprayer or gas-powered sprayer. Contact time, reapplication frequency and rinse method were also varied. In addition to surface removal efficacy, partitioning of contamination between the rinsate and aerosol fractions was determined. Results indicated that pH-adjusted bleach was effective (≥6 logs reduction) when two applications and a 30 min contact time were administered, regardless of the decontaminant application method or material. Spor-Klenz(®) RTU was effective on wood, but achieved ≤3 logs reduction on concrete. A shortened application procedure with pH-adjusted bleach resulted in lower efficacy on wood, and a greater apparent potential for contamination spread. Consideration of material surface type is important when selecting a decontaminant. Also, achieving conditions that effectively inactivate surface biological contamination are critical to preventing the spread of contamination. Results presented here are intended to help development of remediation plans following a biological contamination incident.

Comparison between rinse and crush-and-rub sampling for aerobic bacteria recovery from broiler hatching eggs after sanitization

This study compared surface and deep eggshell aerobic bacteria recovered by the rinse and crush-and-rub sampling methods for commercial hatching eggs after treatment with sanitizers. Eggs were arranged into 5 treatments consisting of no treatment, water, and 3 sanitizers. The sanitizers were H(2)O(2), phenol, and Q(4)B (a compound chemical containing 4 quaternary ammoniums and 1 biguanide moiety). Eggs were sprayed according to treatment and allowed to dry for 1 h before sampling. To collect samples for the eggshell rinse, each egg was massaged in a plastic bag with 20 mL of saline. Eggshells were then aseptically opened and their contents were discarded before being individually crushed into 50-mL centrifuge tubes containing 20 mL of saline. Aerobic bacteria were enumerated on Petrifilm after 48 h of incubation at 37°C. Aerobic bacteria recovered (log(10) cfu/mL) from the eggshell rinse were highest and similar for the no-treatment (4.0) and water (3.7) groups, lower for the phenol (3.2) and H(2)O(2) (3.1) groups, and lowest for the Q(4)B (2.4) group. Aerobic bacteria levels with the crush-and-rub method were similar for the no-treatment (2.5) and water (2.3) groups, lower for the phenol (1.6) group, intermediate for the H(2)O(2) (1.2) group, and lowest for the Q(4)B (0.9) group. The overall correlation between the rinse and crush-and-rub sampling methods for individual egg aerobic bacteria counts was r = 0.71. The correlation within each treatment revealed the following r values: no treatment, 0.55; water, 0.72; H(2)O(2), 0.67; phenol, 0.73; and Q(4)B, 0.38. A second experiment was designed to further examine the lower aerobic bacterial levels recovered by the crush-and-rub method (for previously rinsed eggs) than the levels recovered in the initial eggshell rinse sample. Eggs were either rinsed and then crushed and rubbed, or they were only crushed and rubbed without a prior rinse. Results confirmed a significant decrease (1.5 log(10) cfu/mL) in bacteria levels between the initial rinse (4.4) and the subsequent crush and rub (2.9) for the same eggshell. For the crush-and-rub eggs with no previous rinsing, the bacteria recovery level (3.9) was not significantly different from levels for the rinse method. Therefore, either the rinse or crush-and-rub sampling methods can be used to recover similar levels of eggshell aerobic bacteria.