Toxins ingestion

Caldwell GS, Watson SB, Bentley MG (2004) How to assess toxin ingestion and postingestion partitioning in zooplankton J Plankton Res 26 1369-1377 Cembella AD (2003) Chemical ecology of eukaryotic microalgae in marine ecosystems. Phycologia 42 420 147... 

Symptoms of poisoning may affect all or only few individuals in a particular population. Symptoms may be divided into early, late, and delayed early symptoms occur a few hours after toxin ingestion, late symptoms up to several days after, and delayed symptoms affect patients after some weeks, or even months. The most dangerous situation involves delayed, subacute symptoms that do not affect all individuals in an analyzed population. In such a cases, a relationship between consumed food and disease symptoms is practically impossible to confirm and may lead to a misdiagnosis. 

The onset of symptoms in botulism depends upon the amount of toxin ingested or inhaled and the related kinetics of absorption. Time to onset can range from as early as 2 h to as long as 8 days, although symptoms typically appear between 12 and 72 h after consumption of toxin-contaminated food (Lecour et ah, 1988 Amon et ah, 2001). In a review of 13 foodbome botulism outbreaks involving 50 patients from 1970 to 1984, the incubation period ranged from 10 h to 6 days (Lecour et al, 1988). 

The clinical presentation of human botulism depends on the route of exposure and the rate and amount of toxin absorption. Food-borne botulism has an incubation period ranging from as early as 2h or as long as 8 days after toxin ingestion (36),... 

Martins et al. (2002) investigated the natural co-occurrence of patulin and citrinin on 351 samples of seven apple varieties. The percentage of samples contaminated with patulin only was 68.6%, whereas contamination with citrinin only was 3.9%. Co-occurrence of both mycotoxins occurred in 19.6% of the samples. The maximum mean patulin concentration was 80.5 mg/kg for Richared variety, and the maximum mean citrinin concentration was 0.92 mg/kg for Rome beauty variety. Because the ratio of weight of the rotten area to the total weight was about one-third, a direct risk for myco-toxin ingestion for consumers seems unlikely. Apples with such a high... 

The susceptibility of different animal species to poisoning with castor seed has been shown to vary by as much as 100-fold (Table 17.2) (Hunt et al., 1918 Balint, 1974). It is unclear to what extent this reflects differences in the amount of actual toxin ingested owing to variations in seed content, digestive processes, or protective regurgitation, versus more subtle innate or biochemical mechanisms of resistance to ricin in some animals. 

Finally, nongenetic host differences—including diet, dose of toxin ingested, method of food preparation, and ingestion of particular organs— may also influence the development or progression of illness. 

The mortality rate is dependent on, among other things, timely access to intensive care facilities. In some series, it has approached 60% [133,145]. When death results, it usually occurs within 6 h, and sometimes as rapidly as 17 min, following toxin ingestion. Persons who have not died within 24 h generally recover completely. Similar to PSP, symptoms of tetrodotoxin poisoning usually resolve within 1-2 days and residual impairment has not been reported. The mortality rate from the retrospective analysis of 42 outbreaks of tetrodotoxin-associated paralytic snail poisoning in Asia was 5.2% and 16% had respiratory arrest [140]. 

The above documents the consequences of toxin ingestion. A few reports suggest that inhalation of aerosolized toxin may cause conjunctival irritation, rhinorrhea, respiratory irritation, and possibly exacerbate or cause symptoms similar to reactive airways disease [168, 169]. Several recent studies have provided additional evidence of adverse respiratory effects, including upper airway irritation and discomfort, decreases in pulmonary function parameters, and worsening asthma symptoms, due to occupational and environmental exposures to aerosolized brevetoxins. 

Tetrodotoxication is characterized by a few symptoms of the victims. The type, severity, and range of symptoms depend on the amount of toxin ingested, age, and health of the victim. The four main stages or degrees of tetrodotoxication based are shown in Table V. 

Depending on the amount of toxin ingested, symptoms usually appear within 10-45 minutes of exposure, though some eases have been reported to be a symptomatic until as much as 3 hours after exposure. Oral paresthesia is usually the initial symptom and gradually spreads to the extremities and trunk. Other early symptoms include taste disturbance, dizziness, headaehe, diaphoresis, and papillary symptoms of salivation, hypersalivation, nausea, vomiting, hyperemesis, hematemesis, hypermotility, diarrhea, and abdominal pain. These symptoms are characteristic of first degree of tetrodotoxieation in a system devised by Fukuda and Tani (1941). 

A. Initial dose. Activated charcoal, 1 g/kg (adult dose 50-100 g child < 5 years, 10—25 g) orally or via gastric tube, is administered, or if the quantity of toxin ingested is known, 10 times the amount of ingested toxin by weight is given. For massive overdoses (eg, 60-100 g aspirin), this may need to be given in divided doses over 1-2 days. 

Treatment is supportive in all cases. Critical care management may be required for severe systemic cases. Activated charcoal treatment may be advocated with the rapid recognition of toxin ingestion. 

Symptoms will depend on the dose and duration of exposure and the metHb level attained. S5miptoms and signs are described in Table 5.15. The presence of gastrointestinal symptoms may suggest the possibility of toxin ingestion. 

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