Raw Leafy Vegetables Research Articles

Effects of washing procedures in reducing Listeria monocytogenes on raw leafy vegetables

The efficacy of potable water and antimicrobial agents, including turmeric extract, black pepper extract, sodium chloride and sodium bicarbonate, in reducing Listeria monocytogenes on the leaf mustard (Brassica integrifolia) and iceberg lettuce (Lactuca sativa L.) was compared. The uncontaminated samples of two raw leafy vegetables were inoculated with L. monocytogenes at a concentration of 5 log and 7 log colony-forming units (CFU) g–1 for 1 h. At the high L. monocytogenes contamination level, the treatment with black pepper extract 0.6 mg mL–1 for 5 min was found to produce the most considerable decrease in L. monocytogenes counts, resulting in 1.44 log and 1.68 log reduction on leaf mustard and iceberg lettuce, respectively. Similarly, the black pepper extract also showed the highest L. monocytogenes reduction, approximately 0.79 log CFU g–1 on two leafy vegetables at the low contamination level. However, the odour of black pepper extract was left on the vegetables after being washed.

Vegetable and fruit consumption and cancer of unknown primary risk: results from the Netherlands cohort study on diet and cancer

BackgroundCancer of Unknown Primary (CUP) is a metastatic cancer for which the primary lesion remains unidentifiable during life and little is also known about the modifiable risk factors that contribute to its development. This study investigates whether vegetables and fruits are associated with CUP risk.MethodsWe used data from the prospective Netherlands Cohort Study on Diet and Cancer which includes 120,852 participants aged between 55 and 69 years in 1986. All participants completed a self-administered questionnaire on cancer risk factors at baseline. Cancer follow-up was established through record linkage to the Netherlands Cancer Registry and the Dutch Pathology Registry. As a result, 867 incident CUP cases and 4005 subcohort members were available for case-cohort analyses after 20.3 years of follow-up. Multivariable adjusted hazard ratios were calculated using proportional hazards models.ResultsWe observed no associations between total vegetable and fruit consumption (combined or as separate groups) and CUP risk. However, there appeared to be an inverse association between the consumption of raw leafy vegetables and CUP. With respect to individual vegetable and fruit items, we found neither vegetable nor fruit items to be associated with CUP risk.ConclusionsOverall, vegetable and fruit intake were not associated with CUP incidence within this cohort.

Occurrence of Toxoplasma gondii on Raw Leafy Vegetables in Gaza, Palestine

Toxoplasma gondii, a ubiquitous obligate intracellular parasite that can infect homeothermic animals, is one of the main pathogens causing foodborne diseases worldwide. In Gaza, Palestine, leafy vegetables are frequently eaten raw. The present study was carried out to investigate the occurrence of T. gondii oocyst in local leafy vegetables. Fifty samples each of six species of leafy plants sold in open-air markets, in supermarkets, and by retail sellers were randomly collected from March to August 2019, for a total of 300 samples. The samples were examined by light microscopy after flotation in Sheather's sucrose solution and by PCR assay of the pelleted samples. All suspect T. gondii oocysts were confirmed with a PCR assay. With the PCR assay of the pelleted samples, only 19 (6.33%) of the 300 samples were positive for T. gondii, whereas with the Sheather's flotation method, 35 (11.66%) of the 300 samples were positive. With the PCR assay, among the six plant types mint had the highest T. gondii prevalence (10.00% of samples) followed by watercress and dill (both 8.00%), parsley (6.00%), thyme (4.00%), and lettuce (2.00%). Even though the relative prevalence of T. gondii in the contaminated plant species was similar with both the PCR and Sheather's flotation methods, the actual prevalences were different. With Sheather's flotation, T. gondii prevalence was highest in mint (18.00% of samples) followed by watercress (14.00%), dill (13.00%), parsley (10.00%), thyme (10.00%), and lettuce (6.00%). The relationship between T. gondii contamination and the time of year the samples were collected was also significant. The highest prevalence recorded was in July followed by June and August. These findings indicate that leafy vegetables, particularly mint, can be contaminated with T. gondii and are a potential risk factor for transmitting T. gondii to humans in Gaza, Palestine.

Prevalence and morphological characters of Strongyloides stercoralis contaminating some fresh raw vegetables in Sharkia province, Egypt

Fresh green vegetables are considered an essential source of all nutrients required for a healthy body. However, parasitic contaminations of fresh raw vegetables are common in most developed countries. Therefore, this study explored the prevalence of Strongyloides stercoralis on some fresh raw leafy vegetables in Sharkia province markets because there is not enough data. Raw fresh vegetables of leek (Allium porrum) (n=80) and green onion (Allium ascalonicum) (n=80) were examined. The current study showed that the prevalence of S. stercoralis on leek (Allium porrum) was (60/80) 75% and on green onion (Allium ascalonicum) was (56/80) 70%. Moreover, morphological characters of S. stercoralis were described. Those results revealed that consumption of raw green vegetables represented a high risk of human and animal’s infections with S. stercoralis in Sharkia, Egypt. Hence, effective control measures should be applied to minimize parasitic contaminations of vegetables.

Characterization of Multi-Drug Resistant Gram-Negative Bacteria Present in Fresh Leafy & Salad Vegetables in Dhaka, Bangladesh

This study was conducted to determine the microbiological quality of fresh raw and unwashed leafy and salad vegetables in Dhaka, Bangladesh. Six different types of samples (red amaranth, spinach, carrot, radish, tomato, and cucumber) were collected in pre-sterilized zip-lock bags from various local markets in Dhaka. All samples were transported to the Centre of Excellence for Global Health Research Laboratory of Primeasia University at earliest convenience. Samples were enriched in Nutrient Broth media and were then cultured on selective media for isolation purpose. Serial dilution was performed for the total viable count. Biochemical and carbohydrate profiling was conducted for the presumptive identification of the isolates. Commercial antibiotic discs were used for antibiogram by Kirby-Bauer disc diffusion method on Mueller-Hinton agar medium. The total microbial load ranged from 8x107 to 1.70x108. Total 36 isolates were identified, having 7 differentorganisms. The most predominant organism was Vibrio sp. (23%) followed by Klebsiella sp.(20%), Acinetobacter sp. (19%), Pseudomonas sp. (19%), Salmonella sp. (8%), Moraxella sp.(8%) and Escherichia coli (3%). 11% of the Vibrio sp. isolates were V. cholerae, found from 4 samples. No presence of V. cholerae was observed in the tomatosamples. E. coli was observed only in Carrot sample. Antibiotics from 7 different groups were tested against the organisms among which Imipenem showed the highest sensitivity (86%). Following Ceftriaxone (100%), Nitrofurantoin (94%), Erythromycin (89%) and Amoxicillin (83%) had the highest resistance against the isolated organisms. Moreover, most of the isolates showed a multi-drug resistance pattern where they were resistant to at least four drugs. Prevalence of pathogenic bacteria in raw unwashed vegetables can cause potential adverse health effects and therefore the consumers need to be conscious about the matter.

Characterization of Multi-Drug Resistant Gram-Negative Bacteria Present in Fresh Leafy & Salad Vegetables in Dhaka, Bangladesh

This study was conducted to determine the microbiological quality of fresh raw and unwashed leafy and salad vegetables in Dhaka, Bangladesh. Six different types of samples (red amaranth, spinach, carrot, radish, tomato, and cucumber) were collected in pre-sterilized zip-lock bags from various local markets in Dhaka. All samples were transported to the Centre of Excellence for Global Health Research Laboratory of Primeasia University at earliest convenience. Samples were enriched in Nutrient Broth media and were then cultured on selective media for isolation purpose. Serial dilution was performed for the total viable count. Biochemical and carbohydrate profiling was conducted for the presumptive identification of the isolates. Commercial antibiotic discs were used for antibiogram by Kirby-Bauer disc diffusion method on Mueller-Hinton agar medium. The total microbial load ranged from 8x107 to 1.70x108. Total 36 isolates were identified, having 7 differentorganisms. The most predominant organism was Vibrio sp. (23%) followed by Klebsiella sp.(20%), Acinetobacter sp. (19%), Pseudomonas sp. (19%), Salmonella sp. (8%), Moraxella sp.(8%) and Escherichia coli (3%). 11% of the Vibrio sp. isolates were V. cholerae, found from 4 samples. No presence of V. cholerae was observed in the tomatosamples. E. coli was observed only in Carrot sample. Antibiotics from 7 different groups were tested against the organisms among which Imipenem showed the highest sensitivity (86%). Following Ceftriaxone (100%), Nitrofurantoin (94%), Erythromycin (89%) and Amoxicillin (83%) had the highest resistance against the isolated organisms. Moreover, most of the isolates showed a multi-drug resistance pattern where they were resistant to at least four drugs. Prevalence of pathogenic bacteria in raw unwashed vegetables can cause potential adverse health effects and therefore the consumers need to be conscious about the matter.

Measured cup weights of ten raw leafy vegetables are lower than weights previously reported

Raw dark-green leafy vegetables (LVs) are excellent sources of vitamins A, C, K, folate and manganese. LV intake is reported in cups in the United States (US) and inaccurate cup weights could impact calculated nutrient composition. This project measured the cup weight of ten raw LVs purchased in Coralville, Iowa, compared them to weights reported in two US databases and the Nutrition Facts Label, and assessed changes in nutrient levels for a two-cup serving (one cup-equivalent, c-eq). Six individuals measured one package/head/bunch of each LV. Loosely/moderately packed pieces were weighed in a measuring cup to the nearest 0.1 g. Ready-to-eat produce was measured as purchased; heads/bunches were cut/torn into 2.5-cm pieces. All cup weights were significantly lower than weights previously reported (p < 0.05). Cup weights for seven LVs were <20 g. Highest weights were for Dole® Garden Salad and bok choy. Coefficients of variation between and within measurers were <16% except chopped parsley (35.3% between). LVs except leaf lettuce had one to three fewer nutrients (A, C, folate, manganese) at ≥20% Daily Value for one c-eq at the Iowa cup weight. New Iowa measured cup weights are lower than previously reported, which impacts the calculated nutrient composition.

Prevalence of Enteric Parasites in raw Leafy Vegetables in baghdad city, Iraq

Prevalence of Enteric Parasites in raw Leafy Vegetables in baghdad city, Iraq

Changes in Sensory and Quality Characteristics of S. Aethiopicum (Shum) and A. Lividus (Linn) Leafy Vegetables along the Supply Chain

Changes in sensory attributes of vegetables over time under different conditions have been reported, however, little has been done regarding profiling and assessing changes in sensory attributes of raw leafy vegetables particularly Solanum aethiopicum (S.) and Amaranthus lividus (L.). This study therefore fills an important knowledge gap of profiling sensory attributes and assessing changes in color, texture and appearance of S.aethiopicum and A.lividus leafy vegetables over time after harvest. A complete randomized design in a 3 ×3 factorial arrangement (each vegetable sample was subjected to three treatments (Time of the day) and three replicates) and data was collected by use of quantitative descriptive sensory analysis. Descriptive data was entered into Microsoft excel spread sheets, averages computed and graphs generated. The data was further subjected to ANOVA and a least significant difference test was used to compare means of samples for all attributes at 95% confidence interval. Correlation analysis using Statistical Package for Social Scientients’ (SPSS version 16.0) was also performed to assess relationship between sensory attributes. Descriptive sensory analysis results showed that all 9:00hrs samples were rated highly for each attribute compared to the 12:00hrs and 15:00hrs samples. ANOVA results for S. aethiopicum showed statistical significant (p<0.05) difference for all the attributes except for light green color of leaf stalk (p<0.05) whereas that for A. lividus showed significant differences for moist appearance, well spread appearance, smoothness and overall quality. Correlation results showed significant positive relationship (p<0.05) among attributes. This study observed that sensory attributes of leafy vegetables change with time after harvest andtraders are therefore encouraged to adopt local cooling systems to help preserve the sensory attributes of vegetables.

Prevalence, antimicrobial resistance, resistance genes and class 1 integrons of Salmonella serovars in leafy vegetables, chicken carcasses and related processing environments in Malaysian fresh food markets

This study was carried out to determine the prevalence, antibiotic resistance, resistance genes and class 1 integrons of Salmonella serovars in raw leafy vegetables, chicken carcasses and related environments. From April 2015 to May 2016, a total of 642 samples collected from fresh food markets in Peninsular Malaysia were examined. The overall occurrence of Salmonella species was 29.1% (187/642) with 37 different serovars detected. The most prevalent serovars were S. Corvallis (49/187), S. Brancaster (28/187), S. Weltevreden (17/187), S. Albany (15/187), S. Hvittingfoss (6/178), S. Paratyphi B (6/178) and S. Typhimurium (6/178). Among the Salmonella isolates, the highest antibiotic resistance was to streptomycin (66.6%), followed by tetracycline (44.3%), sulfonamides (44.3%), ampicillin (26.7%), chloramphenicol (29.1%) and trimethoprim-sulfamethoxazole (16.6%). All isolates of Salmonella were 100% susceptible to cephalothin. Fifty-five percent of the isolates (103/187) were multidrug-resistant. The multiple antibiotic resistance (MAR) index of Salmonella serovars ranged from 0.08 to 0.83, and the most prevalent resistance pattern was STeS₃. Eleven out of 16 resistant genes (tetA, tetB, blaTEM-1,temB, strA, strB, aadA, sul1, sul2, floR and cmlA) were detected among the resistant Salmonella isolates. None of the isolates was positive for tetC, tetG, cat1 and cat2. Seventeen isolates harboured class 1 integrons, which were grouped into 5 different integrons profiles (IPs). DNA sequencing analyses have identified dfrA1, dfrA12, aadA2, blaPSE−1, dfrA12-orf-aadA2 arrays of cassettes in variable regions on class 1 integrons.

Knowledge, Awareness and Practices Regarding Cystic Echinococcosis among Livestock Farmers in Basrah Province, Iraq.

Cystic echinococcosis (CE) is an endemic neglected parasitic zoonosis in many of the countries of the Middle East. The disease poses a remarkable economic burden for both animals and humans. In this study, we conducted a questionnaire survey among livestock farmers in Basrah province, southern Iraq, in order to evaluate their knowledge and awareness about CE, and to understand some of the risky practices that could contribute to spread and persistence of such disease. Of the interviewed participants (N = 314), 27.4% owned dogs on their farms. Among farmers owning dogs, 76.7% (66/86) never tied up their dogs, and 43% (37/86) indicated feeding uncooked animal viscera to their dogs. The majority (96.5%) of the farmers indicated that they did not de-worm their dogs at all. Only 9.8% (31/314) of the respondents indicated eating raw leafy vegetables without washing. Added to that, 32% of the interviewees indicated that they source water for domestic use from a river; meanwhile 94.3% (296/314) of them do not boil water before using it for domestic purposes. Half of the interviewed livestock farmers in Basrah were not aware about how humans get infected with CE disease, and 41.4% (130/314) did not even realize that CE is a dangerous disease to human health. Almost one in three of the respondents who owned dogs on their farms viewed de-worming of their dogs as a low priority practice. This study highlights the gap in knowledge and awareness about CE among the study population. Risky practices associated with dog keeping management and food and water handling practices were identified. The insight from this research could be used to improve the delivery of a health education message relevant to cystic echinococcosis control at the human-animal interface in Iraq.

Assessment of pesticide residues and microbial contamination in raw leafy green vegetables marketed in Italy

Vegetables that can be eaten raw in salads are considered at higher risk for contamination by foodborne pathogens and pesticide residues. In this study fresh leafy green vegetables, both pre-cut and uncut, were sampled at retail in all 20 Italian regions and tested for pathogens and pesticide residues contamination.Both in pre-cut and in uncut vegetables 1.00% of samples tested positive for pathogens investigated. Pesticide residues were detected in 53.33% of samples, pre-cut vegetables were more often contaminated (59.06%) than uncut vegetables (47.68%). Samples tested positive from one (monoresidual samples, 27.33%) to seven chemical compounds (multiresidual samples, 26.00%). Maximum Residual Levels (MRL) established by European legislation were exceeded in two multiresidual samples of uncut romaine lettuce (overall non-compliant prevalence 0.67%).A few samples resulted non-compliant for MRL or contaminated by pathogens. Nevertheless in more than half of the samples analysed pesticide residues were found; furthermore vegetables encompassed in this survey are eaten raw and process does not include any effective microbial elimination step. These findings can suggest that public health risk remains, especially regarding pre-cut vegetables.

Parasitological analysis of green leaf lettuce cultivated in different production systems

This study analysed parasite contamination in green leaf lettuce (Lactuca sativa), grown in different cultivation systems (conventional, organic, and hydroponic), from a family farmer cooperative in the municipality of Presidente Prudente, São Paulo, Brazil. Samples were collected at weekly intervals during five months, totalling 180 vegetable samples (60 samples of leaf lettuce from each cultivation system). Lettuce leaves were washed with 0.5% Extran MA 02, and the resulting fluid subjected to sedimentation and centrifugal flotation for recovery of parasite structures. Overall, 71 samples (39.4%) were contaminated with at least one parasite structure, 34 (47.9%) from lettuce grown in the hydroponic system, 20 (28.2%) from the organic system, and 17 (23.9%) from the conventional system. Entamoeba spp. cysts were the most common parasite structures found in the leafy vegetables, with the highest cyst counts found in the hydroponic system (p = 0.003). It is concluded that, regardless of the cultivation system (conventional, organic, or hydroponic), there is a possibility of green leaf lettuce contamination by intestinal parasites. Measures that improve sanitary conditions during production, as well as proper hygiene during the preparation of raw leafy vegetables, may be important to reduce contamination and consequent transmission of parasite diseases from raw leafy vegetable consumption.

Predominance of Giardia duodenalis Assemblage AII in Fresh Leafy Vegetables from a Market in Southern Brazil

We investigated the presence of Giardia duodenalis cysts and its genotypes in raw leafy vegetables sold in a Brazilian market. These products are different from those sold in most street markets because the producers themselves display and sell their products and rely on specialized technical and sanitary assistance. Vegetable and water samples were collected from 14 (80%) producers who cultivated vegetables that are typically consumed raw for sale at the market, obtained at the market and farms, respectively. A total of 128 samples of leafy greens (chives, parsley, cabbage, arugula, watercress, and chicory) and 14 water samples were analyzed by direct immunofluorescence and PCR techniques. The positive samples were genotyped (GHD gene) using PCR and restriction fragment length polymorphism. The analyses indicated that 16 (12.5%) of 128 samples were positive by PCR, while 1 (0.8%) of 128 samples were positive by immunofluorescence. Giardia cysts were not detected in the water samples obtained at the farms. The molecular technique revealed a genotype with zoonotic potential, which underscores the challenge in the control of giardiasis dissemination via the consumption of raw vegetables.

Pesticide residues in leafy vegetables, stalk and stem vegetables from South Korea: a long-term study on safety and health risk assessment

ABSTRACTSouth Korea has a unique food culture. South Koreans enjoy wrapping meat and eating or making kimchi (traditionally fermented Korean food) and eating using raw leafy vegetables, stalk and stem vegetables. Therefore, there is a high chance of being exposed to pesticide residues of vegetables. The objective of this study was to investigate pesticide residues in leafy vegetables, stalk and stem vegetables from South Korea. A total of 8496 samples were mainly collected from Gwangju and Jeonnam area (the largest production region of leafy vegetables, stalk and stem vegetables) in South Korea from 2010 to 2014. A total of 230 pesticides were used for multi-residue analysis of pesticides. Among 8496 samples, 61 different pesticides (1029 times) were detected in 890 samples, of which 118 samples (1.4%) exceeded the Korea maximum residue limits (MRLs). Samples exceeding the MRLs were mostly found in leafy vegetables (brassica lee ssp. namai, leafy lettuce, spinach, perilla leaves, crown daisy, marsh mallow, aster scaber, pimpinella brachycarpa) and Chinese chive. Procymidone, dimethomorph and azoxystrobin were the most frequently found pesticides. A risk assessment of pesticides exceeding the MRLs was evaluated by calculating the estimated daily intake (EDI) and the acceptable daily intake (ADI). The ratio of EDI to ADI was 0.003–30.4%.

New Measured Weight for One Cup Raw Kale Reduces Nutrient Intake of Individuals Following the Wahls™ Diet

Kale is a nutrient-dense, dark-green leafy vegetable often eaten raw in salads or added to smoothies. The USDA National Nutrient Database for Standard Reference Release 26 reports the weight for one cup raw, chopped kale as 67 grams, among the highest for raw leafy vegetables. Objectives: Measure the weight of one cup moderately packed raw kale with stems and tough midrib parts removed and evaluate the impact of the new cup weight on nutrient intake of individuals consumingraw kale. Methods: Six staff members measured curly and lacinato kale using standard procedures and 14 study participantsconsuming 4-6 cups raw leafy vegetables/day measured one cup curly kale in their usual manner. Twenty-seven dietary recalls obtained from participants following the Wahls™ diet were entered intothe Nutrition Data System for Research and then recalculated using staff-measured curly kale cup weight. Results: Mean(SE) staff cup weight for lacinato kale was significantly higher than curly kale [21.3(1.4)g vs 16.0(1.4)g; p<0.0001]. Percent refuse was also higher for lacinato kale [mean(SD) 42.0(11.4)% vs 28.5(3.9)%; p=0.012]. Mean(SD) weight of moderately packed participant-measured cups [17.5(6.4)g]was similar to staff cup weightbutfirmly packed participant cupsweighed more [46.4(4.1)g]. Intake of vitamins K, C, A, manganese, copper, and folatewere significantly lower for diets calculated with the staff cup weight (p<0.0001). Conclusions: The new measured cup weight of raw kale is lower than previously reportedand reduces nutrient levels in diets containing raw kale. Verification of cup weights for other raw leafy vegetables may be warranted.

ADAPTION OF AN IN VITRO DIGESTION METHOD TO EVALUATE CAROTENOID ACCESSIBILITY FROM VEGETABLES

There is evidence that carotenoids, the fat-soluble pigments in fruits and vegetables, are linked to improvements in certain chronic diseases including agerelated macular degeneration, cell-transformation and cardiovascular diseases. It is also known that for humans the bioavailability of carotenoids present in fruits and vegetables is comparatively low and strongly dependent on carotenoid species, chemical structure and food matrix. In this study, an in vitro digestion approach was used to screen the bioaccessible carotenoid content of raw and processed vegetables after three main digestion steps with saliva, gastric- and duodenal juices. The experimental setup was based on the in vitro digestion model of Oomen et al. (2003). First raw or cooked vegetable samples were chopped and incubated at 37°C for 10 min in a shaking water bath with human saliva (pH 6.5; α-amylase). Afterwards, simulation of the gastric phase was achieved by addition of gastric juice (pH 1.0; porcine pepsin) and incubated for an additional 1 h. In a third step, duodenal juice (pH 7.8; porcine pancreatin, porcine lipase) and porcine bile solution (pH 8.0) were added. Samples were then incubated under nitrogen for 2 h, centrifuged and the supernatants were freeze-dried. The six most important nutritional carotenoids (lutein, zeaxanthin, β-crypthoxanthin, α-carotene, β-carotene, lycopene) were quantified by HPLC-UV/VIS. The carotenoids were separated in 47 min on a C30 column with a methanol/MTBE gradient and detected by diode array detection (DAD). Freeze-dried supernatants were redissolved in the eluent, centrifuged and filtered before injection. External standards were used for quantification. In raw green leafy vegetables the carotenoid accessibility was low compared to orange/red colored vegetables and ranged between 4-16% for lutein, 7-25% for zeaxanthin and 12-22% for β-carotene. The bioaccessibility of carotenes and xanthophylls from raw red and orange vegetables was considerably higher and up to 57%. Generally, an increased carotenoid accessibility was observed after thermal processing. This adapted in vitro digestion method is a promising tool to investigate the carotenoid bioaccessibility from vegetables.

Eating Defensively: The Nutrition and Food Safety Benefits of Cooked Produce

Current nutrition trends such as the “raw food diet” may lead consumers to believe that raw leafy vegetables are more nutritious than cooked vegetables, despite research showing that cooked vegetables make important nutritional contributions. This publication describes the nutrient retention and quality of cooked vegetables, explains why cooking vegetables is appropriate for consumers with food safety concerns, and provides tips for preparing cooked vegetables. This 4-page fact sheet was written by Morgan Dehnard, Amy Simonne, and Gail P. A. Kauwell, and published by the UF Department of Family Youth and Community Sciences, October 2013.&#x0D; http://edis.ifas.ufl.edu/fy1395

IRRIGATION WATER AS POSSIBLE SOURCE OF FOOD BORNE PATHOGENS IN RAW VEGETABLES

The effects of different sources of water on the microbial quality of raw leafy vegetables were studied. Two vegetables, lettuce (Lactuca sativa) and fluted pumpkin (Telfairia occidentalis) were planted in a sterile soil in the screen house, irrigated with rain, sewage-polluted stream, tap and well waters, for 60 days and harvested. Coliform and bacterial loads were counted on vegetable leaf surfaces and in the different water samples. The total bacterial counts of vegetable leaf surfaces ranged from 5.46log 10 cfu/g to 6.11log 10 cfu/g while coliform counts ranged from 0.00 to 5.43log 10 cfu/g. The total bacterial counts of the irrigation water samples ranged from 5.60log 10 cfu/ml to 6.12log 10 cfu/ml while coliform counts ranged from 0.00 to 5.48log 10 cfu/ml. Pathogenic bacteria observed in the samples were Escherichia coli, Staphylococcus aureus, Salmonella spp, Shigella dysenteriae, Klebsiella pneumoniae, Aeromonas hydrophila and Enterobacter aerogenes. This study shows that irrigation waters are possible sources of contamination of edible vegetables; therefore the irrigation of food crops with water of unknown microbial quality should be avoided.

Consumption of vegetables and fruits and risk of ovarian carcinoma

To the authors' knowledge, only a few prospective studies to date have investigated the correlation between vegetable and fruit consumption and the risk of ovarian carcinoma and their results have been inconclusive. Vegetable and fruit intake was assessed in relation to ovarian carcinoma, among 62,573 postmenopausal women participating in The Netherlands Cohort Study on Diet and Cancer. Women reported on dietary habits and on other risk factors for cancer in a self-administered questionnaire in 1986. Follow-up of cancer was implemented by annual record linkage with The Netherlands Cancer Registry and a pathology register. After 11.3 years of follow-up, data regarding 252 incident invasive epithelial ovarian carcinoma cases and of 2216 subcohort members were available for case-cohort analyses. Multivariable-adjusted rate ratios (RR) of ovarian carcinoma for women in the highest compared with the lowest quintile of intake (RR(Q5 vs. Q1)) were 0.98 (95% confidence interval [95% CI], 0.61-1.58) for total vegetables and 1.11 (95% CI, 0.70-1.78) for total fruit. The RR(Q5 vs. Q1) values of ovarian carcinoma with intake of cooked vegetables, raw vegetables, brassicas, legumes, cooked leafy vegetables, and raw leafy vegetables were 1.35 (95% CI, 0.83-2.21), 0.75 (95% CI, 0.48-1.18), 1.42 (95% CI, 0.88-2.29), 0.93 (95% CI, 0.60-1.44), 1.05 (95% CI, 0.66-1.67), and 1.23 (95% CI, 0.75-2.02), respectively. With the exception of raw endive (multivariable-adjusted RR, 0.24; 95% CI, 0.07-0.78), none of the individual vegetable or fruit items showed a statistically significant association with ovarian carcinoma. The results of the current study did not support a significant association between vegetable or fruit consumption and ovarian carcinoma risk in a cohort of postmenopausal women.