Microbiological quality of terrestrial gastropods prepared for human consumption.

Hygienic quality was investigated in 60 samples of ready-to-eat snails (Helix lactea, Helix nemoralis, and Helix hortensis) obtained from 30 in-season street stalls and 30 catering establishments (bars) in Córdoba. In accordance with Spanish legislation regarding hygiene in the preparation, distribution, and sale of prepared foods, counts were obtained for total mesophilic aerobic bacteria, coliforms, total Enterobacteriaceae, Escherichia coli, Salmonella, and Staphylococcus aureus. The results obtained showed that 33.3, 20.0, and 13.3% of the samples from stalls and 73.3, 53.3, and 6.7% of the samples from bars did not comply with the regulations with respect to the control of total mesophilic aerobic bacteria, Enterobacteriaceae, and Staphylococcus aureus, respectively. Coliforms were found in 53.3% of the samples from the bars (mean, 2.1 CFU/g) and in 33.3% of the stalls (mean, 1.1 CFU/g). Salmonella was not detected.

PCB congeners transferred by human milk, with an estimate of their daily intake.

The degree of exposure by nursing mothers to individual polychronated biphenyl (PCB) congeners was studied and an estimate made of the daily intake by their infants. Epidemiological data from 100 nursing mothers were collected; 11 individual PCB congeners were determined in samples of the mothers' milk and the toxicity equivalent (TEQ) calculated. The mothers' data and the congener levels were statistically correlated. In over 80% of the samples, PCB congeners nos 180, 28, 138 and 170 were identified, and in over 70%, PCB congeners nos 188, 52, 187 and 153. PCB congeners nos 183, 101 and 118 were identified in percentages of between 39 and 15% of the samples. The highest levels detected were those in PCB no. 28 (1.626 ppb), and the lowest concentrations corresponded to PCB no. 183 (0.109 ppb). The toxicity equivalent (TEQ) was calculated from the toxic equivalent factor (TEF) of the congeners studied. There were no statistical differences between the geographical place of residence, age, occupation, and the congeners studied. There was a significant differentiation with respect to the birthplace, the location of industrial estates and the irrigation facilities in the area of residence, to smoking, the consumption of a varied diet, meat, fish or industrially processed foods, the physical constitution of the mothers, number of children and lactation periods, and PCB congener levels. The total PCB daily intake estimate was under the acceptable daily intake (ADI) limits of tolerance (WHO, 1988), and it was not possible to come to any conclusions for the estimated daily intake (EDI) of the 11 congeners studied since these have not yet been established. It was thus proposed to use the EDIs obtained in order to establish the ADIs of the individual PCB congeners.

Organochlorine pesticides in pasteurized milk and associated health risks.

The presence of organochlorine pesticides (alpha-HCH, beta-HCH, lindane, aldrin, dieldrin, heptachlor, heptachlor epoxide, chlordane and the isomers and metabolites of DDT) in Spanish pasteurized milk were investigated. 95% of the samples contained one of the isomers of the HCH group and 12.9% of them exceeded the maximum residue limit permitted by the European Union; six samples went over that limit for heptachlor epoxide and 74.63% of the samples contained chlordane at higher concentrations than those permitted by the legislation. None of the samples exceeded the limit for the DDT group. The mean concentrations detected for each pesticide were as follows (mg/kg): alpha-HCH = 0.015; beta-HCH = 0.039; lindane = 0.007; delta-HCH = 0.07; aldrin = 0.002; dieldrin = 0.028; chlordane = 0.101; heptachlor = 0.011; heptachlor epoxide = 0.021; o.p'-DDD = 0.016; p.p'-DDD = 0.009; p.p'-DDE = 0.045 (DDT + metabolites = 0.067).

Aflatoxin-producing strains of Aspergillus flavus in the mould flora of the different greenhouse substrates for the cultivation of cucumber (Cucumis sativus, L.).

Fungal contamination in a greenhouse for production of cucumbers (Cucumis sativus, L.) was studied. 158 samples of water, sand, air, leaves and fruits were analyzed. 25 different genera were isolated, the most frequent ones being Pullularia, Aspergillus, Paecilomyces, Alternaria, Fusarium, Rhizopus and Penicillium. Pullularia, Aspergillus, Paecilomyces and Penicillium were present in all types of samples studied. Twenty-one strains of A. flavus were identified and only eight of those produced aflatoxins "in vitro".

Estimates of mean daily intakes of persistent organochlorine pesticides from Spanish fatty foodstuffs.

In many countries pesticide residues in foods are monitored to ensure that public health is not endangered by residue daily intakes in excess of the recommended tolerance levels (van Dokkum and de Vos 1987). In Spain, there is only a total diet study carried out during 1971-72 by Carrasco et al. (1976). In that study, mean daily intakes of 11.5 mu g alpha-HCH, 13.8 mu g lindane and 78.4 mu g DDTs were calculated. Livestock meat and dairy products were the prime sources of human dietary exposure to organochlorines, since between 60-85% of the mean daily intakes arose from these particular food classes. These percentages are in accordance with the well documented fact that organochlorines predominantly accumulate in the lipid fractions of the human food chain, by which animal fatty foods have become a major route of exposure for humans (Kannan et al. 1992). Since the current daily intakes of organochlorines in Spain are not known, it was considered necessary to carry out a pesticide survey in several foods that compose an average Spanish diet. To accomplish that, we have determined residues of a list of priority organochlorine compounds in several fatty foodstuffs collected between 1987 to 1990, and prepared in the way in which they would normally be eaten. This study is merely an attempt to estimate the actual intakes, since only a selected number of food classes were investigated and no age-sex group, or seasonal differences were taken into account. In spite of these disadvantages, there are merits to such an approach. Approximate intake figures are available for comparison with toxicologically acceptable intakes and with retrospective studies in Spain and other countries around the world, and they serve to outline the temporal trends in organochlorine contamination that have occurred during the last decades. Also, it may contribute to diminish the consumer's concern about possible health risks involved in the consumption of food products and help to restore confidence in the quality of our food supply.

Determination of organochlorine pesticides in cheese.

A multiresidue technique was developed for the analysis of 17 organochlorine compounds in cheese: alpha-hexachlorocyclohexane (alpha-HCH), beta-HCH, gamma-HCH, delta-HCH, aldrin, dieldrin, endrin, heptachlor, heptachlor epoxide, chlordane, o,p'- ... (o,p'-DDT), p,p'-DDT, o,p'- ... (o,p'-DDD), p,p'-DDD, o,p'- ... (o,p'-DDE), p,p'-DDE, and the fungicide hexachlorobenzene. In this technique, the fat, previously extracted from the cheeses, was subjected to 2 cleanup and extraction methods: with H2SO4, for acid-resistant organochlorine pesticides, and with KOH-ethanol. The behavior of the compounds in both treatments enabled us to identify the organochlorine pesticides in cheese. The precision (repeatability and reproducibility) and accuracy of the technique were validated.

Organochlorine Pesticides in Spanish Sterilized Milk and Associated Health Risks.

Organochlorine pesticides (α-HCH, ß-HCH, lindane, γ-HCH, aldrin, dieldrin, heptachlor, heptachlor epoxide, clordane, pp'-DDE, op'-DDD, pp'-DDD, op'-DDT, pp'-DDT endrin and methoxychlor) were investigated in Spanish sterilized milks. Ninety percent of the milk samples were found to be contaminated. Thirty-two percent of the samples were contaminated by clordane and showed levels which exceeded the maximum residue limit permitted in the Directive 86/386/EC for organochlorines in milk as calculated on a lipid basis. Aldrin was only found in one sample, while 89.9% of the samples were contaminated by one or more HCH isomers. Mean heptachlor epoxide contamination (0.026 ppm) was approximately 10 times higher than contamination by heptachlor, There is no health risk involved in the consumption of using sterilized milk in Spain.

Mycoflora and toxigenic Aspergillus flavus in Spanish milks.

The isolation, enumeration and identification of moulds were carried out on 64 samples of raw milk and 33 of pasteurized milk. The genera most frequently isolated in the raw milk were: Geotrichum (76.5%), Fusarium (45.3%), and Aspergillus (31.2%). In pasteurized milk they were: Aspergillus (61.5%) followed by Fusarium and Penicillium (37.7% in both cases). A. flavus was found in 12 samples and 1 out of the strains examined produced aflatoxins in vitro. The effect of pasteurization of the milk on spores of A. parasiticus NRRL-2999 was examined. The presence of moulds in pasteurized milk seems to be explained by contamination during bottling.

Mycoflora and toxigenic Aspergillus flavus in Spanish dry-cured ham.

Sixty-five dry-salted hams were analysed. Aspergillus and Penicillium were the dominant genera. In general, the mould flora was dominated by Aspergillus spp. and primarily A. glaucus, A. fumigatus, A. niger and A. flavus. A flavus was found in 16 hams and 9 out of 16 strains examined produced aflatoxins 'in vitro'. Surface samples of dry-salted hams showed growth of inoculated A. parasiticus NRRL-2999 strains and production of aflatoxins in low levels at 25 and 30 degrees C. It is concluded that the presence of toxigenic strains in Spanish dry-salted ham does not constitute a health risk.

Aflatoxin-Producing Strains of Aspergillus flavus in Yogurt.

Fungal contamination was investigated in two batches of commercial yogurt obtained from two different Spanish manufacturers, with special reference to the detection of aflatoxin-producing strains of Aspergillus . The samples were classified into four grades of standard, according to the level of mold present: target, acceptable, doubtful, and reject. The frequency of appearance of different genera of molds in yogurt was also determined. Species of Aspergillus , potential producers of mycotoxins, were frequently identified in the samples analyzed. In seven out of 20 samples (35%), aflatoxin-producing strains of Aspergillus flavus were detected.