During 1985–2005, a total of 91 laboratory-confirmed outbreaks of foodborne botulism occurred in Canada; these outbreaks involved 205 cases and 11 deaths. Of the outbreaks, 75 (86.2%) were caused by Clostridium botulinum type E, followed by types A (7, 8.1%) and B (5, 5.7%). Approximately 85% of the outbreaks occurred in Alaska Native communities, particularly the Inuit of Nunavik in northern Quebec and the First Nations population of the Pacific coast of British Columbia. These populations were predominantly exposed to type E botulinum toxin through the consumption of traditionally prepared marine mammal and fish products. Two botulism outbreaks were attributed to commercial ready-to-eat meat products and 3 to foods served in restaurants; several cases were attributed to non-Native home-prepared foods. Three affected pregnant women delivered healthy infants. Improvements in botulism case identification and early treatment have resulted in a reduction in the case-fatality rate in Canada.

The distribution and levels of Clostridium botulinum type E were determined from field sites used by Inuit hunters for butchering seals along the coast of Nunavik. The incidence rates of C. botulinum type E in shoreline soil along the coast were 0, 50, and 87.5% among samples tested for the Hudson Strait, Hudson Bay, and Ungava Bay regions, respectively. Spores were detected in seawater or coastal rock surfaces from 17.6% of butchering sites, almost all of which were located in southern Ungava Bay. Concentrations of C. botulinum type E along the Ungava Bay coast were significantly higher than on the coasts of Hudson Strait and Hudson Bay, with the highest concentrations (270 to 1,800/kg of sample) found near butchering sites located along the mouths of large rivers. The Koksoak River contained high levels of C. botulinum type E, with the highest median concentration (270/kg) found in sediments of the marine portion of the river. C. botulinum type E was found in the intestinal contents (4.4%) and skins (1.4%) of seals. A high genetic biodiversity of C. botulinum type E isolates was observed among the 21 butchering sites and their surroundings along the Nunavik coastline, with 83% of isolates (44/53) yielding distinct pulsed-field gel electrophoresis genotypes. Multiple sources of C. botulinum type E may be involved in the contamination of seal meat during butchering in this region, but the risk of contamination appears to be much higher from environmental sources along the shoreline of southern Ungava Bay and the sediments of the Koksoak River.

Among 27 mold isolates from decaying tomatoes, culture filtrates or ethyl acetate extracts of 8 isolates grown in yeast extract-sucrose medium were markedly toxic (mortality, >50%) to brine shrimp larvae. The toxicity of six of these isolates could be attributed to the presence of citrinin, tenuazonic acid, or T-2 toxin. Ethyl acetate extracts of five Alternaria isolates and one Fusarium isolate were mutagenic for Salmonella typhimurium strains. In ripe tomatoes inoculated with toxin-producing isolates and incubated at 25°C, one Alternaria alternata isolate produced tenuazonic acid in seven of seven tomatoes at levels of up to 106 [Lg/g and alternariol methyl ether in one of the seven tomatoes at 0.8 ,tg/g. Another A. alternata isolate produced tenuazonic acid or alternariol methyl ether at much lower levels in only three of seven tomatoes. Patulin and citrinin were produced by a Penicillium expansum isolate at levels of up to 8.4 and 0.76 ,ug/g, respectively. In tomatoes incubated at 150C, a Fusarium sulphureum isolate produced T-2 toxin, HT-2 toxin, and neosolaniol at levels of up to 37.5, 37.8, and 5.6 jtg/g, respectively. If these mycotoxins are thermostable, they may occur at detectable levels in tomato products whenever partially moldy tomatoes are used as raw material.

The retention, distribution, excretion, and metabolism of dibutyl phthalate-7-14C have been investigated in the rat. Of a single oral dose 80-90% is metabolized and excreted in the urine within 48 hr. Phthalic acid, monobutyl phthalate, monO(3hydroxybutyl) phthalate, and mono(4-hydroxy-butyl) phthalate have been identified as metabolites in the urine. Rats fed for 12 weeks on a diet containing dibutyl phthalate a t 1 g/kg of feed did not accumulate either dibutyl phthalate or monobutyl phthalate in tissues or organs.Phthalate esters have become ubiquitous contaminants of the environment and their occurrence, analysis, toxicology, and health hazards have been extensively reviewed (Autian, 1973;Bloom, 1972). Dibutyl phthalate (DBP) has been reported in air samples (Thomas, 1973), inland waters (Hites, 1973), and fish (Mayer et al., 1972;Williams, 1973). It has a low oral toxicity (Lefaux, 1968) but has been reported to have some toxic properties (Singh et al., 1972). Chambon et al. (1972) have reported that rats orally dosed with DBP excrete monobutyl phthalate (BP) and phthalic acid in the urine but accounted for only 2-3% of the ingested dose. Stalling et al. (1973) have shown that DBP is metabolized, by a microsomal preparation from channel catfish liver, to B P and at least three other unidentified metabolites. Albro and Moore (1974) have investigated the metabolism of several phthalate diesters and have identified, by infrared and mass spectrometry, six metabolites in the urine of rats dosed with DBP. They were able to account for only 28% of the ingested dose and the present study has, therefore, been carried out using DBP-7-14C in order to quantitate the retention, distribution, excretion, and metabolism in the rat. EXPERIMENTAL SECTION

A survey of 38 samples of Canadian overwintered grains showed that 14 (37%) contained viable Fusarium. Of a total of 38 Fusarium isolates, cultured on autoclaved corn, 20 (from 7 grain samples) showed toxicity to brine shrimp larvae and 12 (from 5 samples) produced levels of trichothecenes detectable by thin layer chromatography. The principal trichothecene found was T-2 toxin, produced by 10 strains and accompanied in half of these by neosolaniol; some of these strains were identified as F. sporotrichioides Sherbakoff. Two strains of F. poae (Peck) Wollenw. formed small amounts of diacetoxyscirpenol. T-2 toxin was the most toxic of 8 trichothecenes tested on brine shrimp larvae; the wide range of toxicities limits the usefulness of this bioassay as a general screening method for trichothecenes.