Pathways and factors for food safety and food security at PFOS contaminated sites within a problem based learning approach

Perfluorooctanesulfonic acid (PFOS) and related substances have been listed in Annex B of the Stockholm Convention. The implementation requires inventories of use, stockpiles, and environmental contamination including contaminated sites and measures for (risk) reduction and phase out. In most countries monitoring capacity is not available and therefore other approaches for assessment of contaminated sites are needed. Available informations about PFOS contamination in hot spot areas and its bio-accumulation in the food webs have been merged to build up a worst-case scenario We model PFOS transfer from 1 to 100ngL(-1) range in water to extensive and free-range food producing animals, also via the spread of contaminated sludges on agriculture soils. The modeling indicates that forages represented 78% of the exposure in ruminants, while soil accounted for >80% in outdoor poultry/eggs and pigs. From the carry-over rates derived from literature, in pork liver, egg, and feral fish computed concentration falls at 101, 28 and 2.7ngg(-1), respectively, under the 1ngL(-1) PFOS scenario. Assuming a major consumption of food produced from a contaminated area, advisories on egg and fish, supported by good agriculture/farming practices could abate 75% of the human food intake. Such advisories would allow people to become resilient in a PFOS contaminated area through an empowerment of the food choices, bringing the alimentary exposure toward the current Tolerable Daily Intake (TDI) of 150ngkg(-1)bodyweightd(-1) proposed by the European Food Safety Authority (EFSA).

National outbreak of Salmonella Enteritidis phage type 14b in England, September to December 2009: case-control study

We conducted an unmatched retrospective case–control study to investigate an upsurge of non-travel-related sporadic cases of infection with Salmonella enterica subsp. enterica serotype Enteritidis phage type 14b with antimicrobial resistance to nalidixic acid and partial resistance to ciprofloxacin (S. Enteritidis PT 14b NxCp(L)) that was reported in England from 1 September to 31 December 2009. We analysed data from 63 cases and 108 controls to determine whether cases had the same sources of infection as those found through investigation of 16 concurrent local foodborne outbreaks in England and Wales. Multivariable logistic regression analysis adjusting for age and sex identified food consumption at restaurants serving Chinese or Thai cuisine (odds ratio (OR): 4.4; 95% CI: 1.3–14.8; p=0.02), egg consumed away from home (OR: 5.1; 95% CI: 1.3–21.2; p=0.02) and eating vegetarian foods away from home (OR: 14.6; 95% CI: 2.1–99; p=0.006) as significant risk factors for infection with S. Enteritidis PT 14b NxCp(L). These findings concurred with those from the investigation of the16 outbreaks, which identified the same Salmonella strain in eggs from a specified source outside the United Kingdom. The findings led to a prohibition of imports from this source, in order to control the outbreak.

Tetrodotoxin poisoning following ingestion of the toxic eggs of the horseshoe crab Carcinoscorpius rotundicauda, a case series from 1994 through 2006

Between 1994 and 2006, a total of 280 cases of varying degrees of tetrodotoxin poisoning following ingestion of the toxic eggs of the horseshoe crab, Carcinoscorpius rotundicauda, were admitted to the medical service of Chon Buri Hospital. The severity of the poisoning was classified into four stages based on clinical signs and symptoms of human tetrodotoxication. Of 245 available medical records; 100 were in stage 1, 74 were in stage 2, 3 were in stage 3 and 68 were in stage 4. The frequencies of symptoms and signs included the following : circumoral and lingual numbness (98%), hands and feet numbness (94.7%), weakness (59.6%), dizziness and vertigo (54.3%), nausea and vomiting (52.6%), transient hypertension (39.6%), respiratory paralysis (27.7%), fixed dilated pupils (14.7%), ophthalmoplegia (12.2%), blood pressure lower than 90/60 mmHg (5.7%), and polyuria (0.4%). All patients received symptomatic and supportive treatment. Endotracheal intubation and mechanical ventilation were considered when paralysis was progressing rapidly. The results of treatment are as follows: 239 patients (97.5%) showed complete recovery, 5 patients (2%) died, and 1 patient (0.4%) suffered anoxic brain damage. Horseshoe crab poisoning occurs both sporadically and epidemically in Chon Buri. Seasonal variation in the number of cases of poisoning was observed with a peak from December through March.

Life-threatening episode after ingestion of toad eggs: a case report with literature review

It is known that toad possesses several toxic substances in the skin and parotid glands. In the past, toad-venom poisoning had been reported from ingestion of toad soup, Kyushin and aphrodisiac pills, but the poisoning from toad eggs is observed for the first time. The case of a healthy female who had previously eaten toad soup twice without any discomfort is reported. She developed gastrointestinal symptoms and life-threatening cardiac rhythm after ingestion of toad eggs.

Influence of holding temperature on the growth and survival of Salmonella spp. and Staphylococcus aureus and the production of staphylococcal enterotoxin in egg products

In this study, growth and survival of Salmonella spp. and Staphylococcus aureus in steamed egg and scrambled egg held at 5, 18, 22, 37, 55 and 60 degrees C are investigated. The production of staphylococcal enterotoxin in steamed egg is also examined. Results reveal that Salmonella spp. and Staph. aureus in the egg products multiply best at 37 degrees C, followed closely by 22 and 18 degrees C. Neither pathogen showed growth in the egg products held at 5 degrees C. Initial inoculation dose, holding temperature and holding time affected the population of both organisms found in the egg products. Staphylococcal enterotoxin A (SEA) and B (SEB) are detected only in the egg products held at 37 or 22 degrees C. After holding at 37 degrees C for 36 h, scrambled egg inoculated with ca. 5.0 log cfu/g Staph. aureus contains the highest levels of SEA (> 64 ng/g) and SEB (> 64 ng/g). Although Salmonella spp. and Staph. aureus grow better in steamed eggs than in scrambled eggs, production of staphylococcal enterotoxin, in general, was higher in scrambled eggs than in steamed eggs. On the other hand, a repaid destruction of the test organisms in steamed eggs held at 60 degrees C was observed. Holding the steamed eggs at 60 degrees C, Salmonella spp. and Staph. aureus with an initial population of ca. 5.9 and 5.6 log cfu/g, respectively, reduced to a non-detectable level in 1 h.

Foodborne botulism from eating home-pickled eggs--Illinois, 1997

During November 1997, the Illinois Department of Public Health was notified by a local physician about a possible case of foodborne botulism. This report summarizes the case investigation, which implicated home-pickled eggs as the cause.

[Puffer fish poisoning]

We report three cases of a collective tetrodotoxin poisoning, after ingestion of puffer fish eggs. This neurotoxin is the most potent membrane stabilizer, blocking the nervous conduction and resulting in death from respiratory paralysis in case of massive ingestion. The father died at admission, the mother and her daughter presented an acute respiratory failure and a flaccid tetraplegia, with favourable outcome after 24 hours.

An outbreak of food poisoning associated with restaurant-made mayonnaise in Abha, Saudi Arabia

In May 1996, an outbreak of gastroenteritis occurred among customers who bought dinner from a restaurant that specialised in fried chicken in Abha city, south-west Saudi Arabia. The median incubation period was 10 hours (range: 3 to 27 hours). Of the 10 food items served, only mayonnaise (RR 2.52; 95% CI 1.71-3.73) and minced garlic (RR 1.20; 95% CI 1.02-1.41) were associated with cases. Salmonella enterica was isolated from 124 (84%) of the 159 persons with symptoms of food poisoning, and 91 (73%) were serogroup Enteritidis, phage type B 14. Mayonnaise was prepared in the restaurant using a regular blender. Minced garlic was prepared with the same blender immediately after making the mayonnaise. Unsafe storage of the mayonnaise at room temperature for a median of 6 hours could have resulted in overgrowth of bacteria and a high infective dose of bacteria per serving.

An outbreak of horseshoe crab poisoning in Chon Buri, Thailand: clinical, toxicologic and therapeutic considerations

In 1994-1996, an outbreak of horseshoe crab poisoning by eating toxic eggs of the horseshoe crab Carcinoscorpius rotundicauda affected over 100 persons in Chon Buri which located on the eastern coast of Thailand. We discuss clinical description and management of this first major outbreak. The responsible toxin has been partially purified by means of ultrafiltration and high performance liquid chromatography. The horseshoe crab toxin is identified as tetrodotoxin (TTX) and anhydro TTX.

An epidemic of tetrodotoxin poisoning following ingestion of the horseshoe crab Carcinoscorpius rotundicauda

At certain seasons of the year in Thailand, the horseshoe crab Carcinoscorpius rotundicauda may be toxic to human and fatal poisoning occasionally occur. Tetrodotoxin (TTX) and its derivatives were major toxins in the toxic eggs of the horseshoe crab. An epidemic of poisoning by eating toxic eggs of the horseshoe crab affected 71 persons in Chon Buri which located in the eastern coast of Thailand. Patients generally presented with neurologic symptoms such as paresthesia, vertigo, weakness, respiratory paralysis, altered consciousness with unreactive dilated pupils in addition to gastrointestinal symptoms such as nausea and vomiting. Nineteen patients required artificial ventilation and there were two deaths. This is the first large outbreak of tetrodotoxin poisoning recognized in Thailand.

Outbreak of Salmonella enteritidis infection associated with consumption of raw shell eggs, 1991

Salmonella enteritidis (SE) is the most frequently reported Salmonella serotype in the United States. From January through December 1991, state health departments reported 66 outbreaks of SE in the United States to CDC. This report describes an SE outbreak associated with consumption of raw shell eggs and underscores the necessity of adequately cooking shell eggs.

[A study on phage analysis of two episodes of food poisoning caused by the same serotype of enteroinvasive Escherichia coli]

The strains of EIEC serotype O28ac:K73 (B):H-were isolated from two episodes of food poisoning in Beijing during July to September in 1984. All strains were examined by E. coli K12 and found that they possessed the ability to produce the same colicin and same phage sensitivity pattern to eight phages isolated from contaminated water in Beijing area. These characteristics were different from reserved strains O28ac and other strains of E. coli. It indicated that two episodes were caused by the same phage type of O28ac:K73 (B):H-and proved the local outbreak was caused by same strain in western area of Beijing. The authors discussed in detail. The differentiation methods for plaque formation produced by colicin and phage.

An outbreak of salmonellosis amongst holidaymakers in Madeira, July 1988

In July 1988, 20 of 49 tourists from Northern Ireland became ill with gastrointestinal symptoms while on holiday in Madeira and four were admitted to hospital. Salmonella enteritidis was subsequently isolated from eight members of the party. Epidemiological investigations implicated fried and/or scrambled eggs as the vehicle of infection.

Large outbreak of food poisoning caused by Salmonella typhimurium definitive type 49 in mayonnaise

An investigation was conducted to determine the vehicle of infection of an outbreak of food poisoning in a large metropolitan building early in 1988. A questionnaire was distributed to 700 people who had eaten in the building during the week of the outbreak, and attack rates for specific food were calculated. Food and stool samples, environmental samples, and eggs and environmental swabs from the egg suppliers were examined microbiologically. Altogether 474 questionnaires were returned, 120 people reporting gastrointestinal illness. The illness was significantly associated with foods containing mayonnaise. Salmonella typhimurium definitive type 49 was isolated from 76 of the 84 stool samples containing salmonella and from five of the eight samples taken from the chicken house of the main egg supplier. Mayonnaise was probably the vehicle of infection, which was caused by S typhimurium definitive type 49.

Staphylococcal food poisoning associated with an Easter egg hunt

Staphylococcal contamination of intact, hard-boiled eggs resulted in the food poisoning of an estimated 300 children out of 850 who had participated in an Easter egg hunt. Enterotoxigenic staphylococci that were isolated from the Easter eggs matched that obtained from an infected cook who prepared the eggs three to five days before the hunt and which he left unrefrigerated. Experimental studies demonstrated that heated eggs can absorb 2 mL of contaminated cool water through intact eggshells. When water was inoculated with pathogenic staphylococci at even low contamination levels, rapid growth and enterotoxin production within cooked eggs could be easily duplicated. This is the first large outbreak of its type; safeguards can and should be employed to prevent future ones.

An outbreak of salmonellosis associated with a fatality in a healthy child: a large dose and severe illness

In June 1982, an outbreak of Salmonella gastroenteritis occurred on a farm in Wyoming. All eight affected persons became severely ill 8-18 hours after they had eaten homemade ice cream. A previously healthy 13-year-old boy died 37 hours after exposure; his mother and four younger siblings were transferred to intensive care units in hospitals in adjoining states, and the remaining two adult males were hospitalized locally. Salmonella typhimurium was isolated from all eight ill persons, from the remaining ice cream, and from the family's hens whose eggs were used in the preparation of the ice cream. All Salmonella contained identical plasmids (60-, 5.6-, and 3.3-megadalton); the ice cream contained 10(6) salmonellae/g and, according to food histories, individuals consumed an estimated dose of between 10(8) and 10(9) organisms. The fatal illness occurred in the boy who had eaten the largest amount of ice cream (10(9) organisms). This report demonstrates that Salmonella can cause fatal illness in previously healthy individuals and that the incubation period and the severity of the illness may be related to the dose.