Local and Traditional Ecological Knowledge of Fish Poisoning in Fiji.

Fish poisoning (FP) affects human health, trade and livelihood in Fiji, where management has depended mainly on traditional ecological knowledge (TEK). This paper investigated and documented this TEK through a 2-day stakeholder workshop, group consultation, in-depth interviews, field observations, and analyses of survey data from the Ministry of Fisheries, Fiji. Six TEK topics were identified and classified as preventative and treatment options. The preventive approach involves identifying toxic reef fishes, the spawning season of edible seaworms, hotspot areas of toxic fishes, folk tests, and locating and removing toxic organs. For example, 34 reef fish species were identified as toxic. The FP season was associated with the spawning of balolo (edible seaworm) and the warmer months of October to April (cyclone seasons). Two well-known toxic hotspots associated with an abundance of bulewa (soft coral) were identified. Folk tests and locating and removing toxic fish organs are also practised for moray eels and pufferfish. At the same time, various locally available herbal plants are used to treat FP as the second line of defence. The TEK collated in this work can help local authorities better identify the sources of toxicity, and applying TEK preventive measures could stem the tide of fish poisoning in Fiji.

Polynesian medicine used to treat diarrhea and ciguatera: An ethnobotanical survey in six islands from French Polynesia.

ETHNOPHARMACOLOGICAL RELEVANCE: In French Polynesia, many pathologies common or endemic to the territory cause diarrhea. This is the case for rotavirus gastroenteritis, salmonella food poisoning, ingestion of water contaminated by bacteria, and ciguatera. To treat these ailments, the population may employ traditional medicine for cultural reasons, geographical isolation, and poor health coverage. Polynesian remedies are often used without medical consultation and there is no data on their benefit-risk balance. A few ethnobotanical studies have been carried out in order to identify the traditional remedies used for various ailments, but few studies have focused on gastrointestinal pathologies. In this context, an ethnobotanical survey was carried out to identify treatments used for diarrhea and ciguatera, inventory the plants used, better understand the local representation of these remedies, and provide efficacy and safety data on these uses. MATERIALS AND METHODS: From February to April 2021, a semi-structured survey was conducted on six islands in French Polynesia, including one island in the Windward Islands archipelago (Tahiti), three islands in the Marquesas archipelago (Hiva Oa, Nuku Hiva, Tahuata), and two islands in the Leeward Islands archipelago (Raiatea, Tahaa). A total of 133 people was interviewed including 34 specialists (of which 29 experts in herbalism). RESULTS: These people mentioned the use of 27 plants for the treatment of diarrhea, and 24 for the treatment of ciguatera. Citrus aurantiifolia, Psidium guajava and Cordyline fruticosa were the three most cited plant species used for treating diarrhea, while Cocos nucifera, Punica granatum and Barringtonia asiatica were the most cited for ciguatera. A large majority of plants are widespread and introduced plants, which is congruent with the history of Polynesian people. While some plants are well known for similar uses (e.g. Psidium guajava for diarrhea, Heliotropium arboreum for ciguatera), others are less well known and may present toxicity risks (e.g. Barringtonia asiatica for ciguatera). CONCLUSION: Traditional Polynesian medicine is an integral part of the local culture so important to be preserved and valued. However, more pharmacological and toxicological studies are still needed to determine the benefit-risk balance of some of these remedies and to allow their official integration into the Polynesian health system.

Effects of pH and Nutrients (Nitrogen) on Growth and Toxin Profile of the Ciguatera-Causing Dinoflagellate Gambierdiscus polynesiensis (Dinophyceae).

Ciguatera poisoning is a foodborne disease caused by the consumption of seafood contaminated with ciguatoxins (CTXs) produced by dinoflagellates in the genera Gambierdiscus and Fukuyoa. Ciguatera outbreaks are expected to increase worldwide with global change, in particular as a function of its main drivers, including changes in sea surface temperature, acidification, and coastal eutrophication. In French Polynesia, G. polynesiensis is regarded as the dominant source of CTXs entering the food web. The effects of pH (8.4, 8.2, and 7.9), Nitrogen:Phosphorus ratios (24N:1P vs. 48N:1P), and nitrogen source (nitrates vs. urea) on growth rate, biomass, CTX levels, and profiles were examined in four clones of G. polynesiensis at different culture age (D10, D21, and D30). Results highlight a decrease in growth rate and cellular biomass at low pH when urea is used as a N source. No significant effect of pH, N:P ratio, and N source on the overall CTX content was observed. Up to ten distinct analogs of Pacific ciguatoxins (P-CTXs) could be detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in clone NHA4 grown in urea, at D21. Amounts of more oxidized P-CTX analogs also increased under the lowest pH condition. These data provide interesting leads for the custom production of CTX standards.

Ciguatoxins activate the Calcineurin signalling pathway in Yeasts: Potential for development of an alternative detection tool?

Ciguatoxins (CTXs) are lipid-soluble polyether compounds produced by dinoflagellates from the genus Gambierdiscus spp. typically found in tropical and subtropical zones. This endemic area is however rapidly expanding due to environmental perturbations, and both toxic Gambierdiscus spp. and ciguatoxic fishes have been recently identified in the North Atlantic Ocean (Madeira and Canary islands) and Mediterranean Sea. Ciguatoxins bind to Voltage Gated Sodium Channels on the membranes of sensory neurons, causing Ciguatera Fish Poisoning (CFP) in humans, a disease characterized by a complex array of gastrointestinal, neurological, neuropsychological, and cardiovascular symptoms. Although CFP is the most frequently reported non bacterial food-borne poisoning worldwide, there is still no simple and quick way of detecting CTXs in contaminated samples. In the prospect to engineer rapid and easy-to-use CTXs live cells-based tests, we have studied the effects of CTXs on the yeast Saccharomyces cerevisiae, a unicellular model which displays a remarkable conservation of cellular signalling pathways with higher eukaryotes. Taking advantage of this high level of conservation, yeast strains have been genetically modified to encode specific transcriptional reporters responding to CTXs exposure. These yeast strains were further exposed to different concentrations of either purified CTX or micro-algal extracts containing CTXs. Our data establish that CTXs are not cytotoxic to yeast cells even at concentrations as high as 1µM, and cause an increase in the level of free intracellular calcium in yeast cells. Concomitantly, a dose-dependent activation of the calcineurin signalling pathway is observed, as assessed by measuring the activity of specific transcriptional reporters in the engineered yeast strains. These findings offer promising prospects regarding the potential development of a yeast cells-based test that could supplement or, in some instances, replace current methods for the routine detection of CTXs in seafood products.

Is mannitol the treatment of choice for patients with ciguatera fish poisoning?

CONTEXT: Ciguatera fish poisoning arises primarily from consumption of carnivorous reef fish caught in tropical and sub-tropical waters. Ciguatoxins, a class of tasteless, heat-stable, polycyclic toxins produced by dinoflagellates, accumulate through the food chain and concentrate in various carnivorous fish, such as groupers, barracudas, wrasses, amberjack, kingfishes, and eels. Characteristics of ciguatera fish poisoning include early nausea, vomiting, and diarrhea in the first one to two days post ingestion, followed by the appearance of sensory disturbances. The classic dysaesthesia is cold allodynia, often described as reversal of hot and cold sensation, but a more accurate description is burning pain on exposure to cold. OBJECTIVE: To discuss and appraise the evidence regarding the use of mannitol or other drugs in treating ciguatera framed in the historical context of the last four decades. METHODS: We searched PubMed and Embase for all years from 1966 to March 31, 2017 with search terms "ciguatera", "mannitol", and "treatment". These searches identified 85 articles, of which 36 were relevant to the review question. We searched Google Scholar to supplement the primary search and reviewed the references of articles for sources overlooked in the original searches. These secondary searches identified another 23 references. We excluded six clinical reports (two case series and four case reports) which did not clearly describe ciguatera or which lacked information on treatment or outcome. Fifty-three clinical articles remained for review. We searched PubMed using "ciguatera" AND "treatment" NOT "mannitol" to better identify reports describing other treatments. The search identified 128 articles, of which nine described specific pharmacological treatments and their outcomes. We combined our findings into a consensus review of the evidence both for and against the use of mannitol or other medications for ciguatera fish poisoning. Early human evidence of effectiveness of mannitol: A 1988 report described an unexpected discovery that intravenous mannitol could rapidly and effectively treat ciguatera fish poisoning. Several other uncontrolled case series and case reports appeared to support the use of mannitol. In 2002, a small randomized, controlled trial reported no significant difference between mannitol and normal saline. Subsequent case reports have cited this study as the reason for or to withhold mannitol. Thus, some controversy exists regarding whether mannitol is useful or not for treating ciguatera fish poisoning. Basic science and animal research on ciguatera and mannitol: In vitro experiments of isolated neurons demonstrate that ciguatoxins produce neuronal edema, open certain sodium channels, block potassium channels, cause uncontrolled and repetitive action potentials after a stimulus. Addition of mannitol decreases the edema and reduces the uncommanded action potentials. However, intraperitoneal injection of ciguatoxin in rats increases neuronal refractory period and slows nerve conduction velocity. Treatment with mannitol fails to correct these effects. Comparative trials of mannitol: Evidence supporting mannitol for ciguatera fish poisoning includes four uncontrolled case series, one prospective, unblinded comparative trial and several case reports. Evidence against mannitol consists of one RCT, which has a small sample size and several potential limitations. Empirical human experience with other treatments: Evidence regarding other treatments consists only of ten case reports and three overlapping case series that describe using amitriptyline, fluoxetine, duloxetine, gabapentin, pregabalin, or tocainide. For each of these, a long duration of treatment appears to be necessary to maintain symptomatic improvement. None of these treatments has been shown to be superior to mannitol. CONCLUSIONS: It is reasonable to consider using intravenous mannitol in cases of acute ciguatera fish poisoning. Medications used in other neuropathic syndromes appear to suppress the paresthesiae of persistent ciguatera cases. However, the human evidence is of low quality for all treatments.

Ciguatera fish poisoning: Incidence, health costs and risk perception on Moorea Island (Society archipelago, French Polynesia).

Ciguatera Fish Poisoning (CFP) is a non-bacterial seafood poisoning well characterized in the remote archipelagos of French Polynesia, yet poorly documented in the Society archipelago, most notably on Moorea, the second most populated island in French Polynesia, which counts a high proportion of fishermen fishing on a regular basis. To address this knowledge gap, a holistic study of the ciguatera issue was conducted on Moorea. First, ciguatera risk was analysed in terms of incidence rate, fish species most commonly involved and risk stratification in Moorea lagoon based on 2007-2013 epidemiological data. A mean incidence rate of 8 cases per 10,000 inhabitants for the study period and an average under-reporting rate of 54% were found. Taking into account hospitalization and medication fees, and loss of productive days, the health-related costs due to CFP were estimated to be USD $1613 and $749 for each reported and unreported case, respectively, with an overall cost of USD $241,847 for the study period. Comparison of the present status of CFP on Moorea with a risk map established in the late 1970's showed that the spatial distribution of the risk has stayed relatively stable in time, with the north shore of the island remaining the most prone to ciguatera. Evaluation of the current knowledge on CFP among different populations groups, i.e. fishermen, residents and visitors, was also conducted through direct and indirect interviews. About half of the fishermen interviewed were actually able to identify risky fishing areas. While, overall, the CFP risk perception in the fishing community of Moorea seemed accurate, although not scientifically complete, it was sufficient for the safe practice of their fishing activities. This may be due in part to adaptive responses adopted by 36% of the fishermen interviewed, such as the avoidance of either high-risk fishing sites or toxic species. At the residents and visitors' level, the study points out a striking lack of awareness of the CFP issue among visitors, as compared to local residents. Indeed, less than 25% of Moorea visitors vs. an average of 98% in residents were aware of CFP or of its presence on the island. Interestingly, evaluation of the fish consumption preferences showed that 70% of visitors do not consume lagoon fish during their stay, not for fear of CFP, but mainly due to the lack of availability of these species in recreational facilities or because they have nutritional preference for pelagic fish. This lack of awareness, along with the report by several CFP patients of the consumption of fish species yet banned for sale, stress the need for improved communication efforts on this critical issue among both residents and visitors on Moorea. The implementation of a public outreach strategy is proposed, based on both existing information networks and low-cost communication actions through information displays at various strategic locations, e.g. Tahiti-Faa'a international airport, the ferry boat station, recreational facilities, as well as the major trading points on Moorea Island.

Neurotoxicity and reactive astrogliosis in the anterior cingulate cortex in acute ciguatera poisoning.

Ciguatoxins (CTXs) cause long-term disturbance of cerebral functions. The primary mechanism of neurotoxicity is related to their interaction with voltage-gated sodium channels. However, until now, the neurological targets for CTXs in the brain of intact animals have not been described. In our study, 1 day following oral exposure to 0.26 ng/g of Pacific ciguatoxin 1 (P-CTX-1), we performed in vivo electrophysiological recordings in the rat anterior cingulate cortex (ACC) and identified the increase in spontaneous firings and enhanced responses to visceral noxious stimulation. Local field recordings characterized the P-CTX-1-induced synaptic potentiation and blockage of the induction of electrical stimulation-induced long-term potentiation in the medial thalamus (MT)-ACC pathway. Furthermore, intracerebroventricular administration of P-CTX-1 at doses of 1.0, 5.0, and 10 nM produced a dose-dependent increase in ACC neuronal firings and MT-ACC synaptic transmission. Further studies showed upregulated Na(+) channel expression in astrocytes under pathological conditions. We hypothesized that the astrocytes might have been activated in the ciguatera poisoning in vivo. Increases in glial fibrillary acid protein expression were detected in reactive astrocytes in the rat ACC. The activation of astroglia was further indicated by activation of the gap junction protein connexin 43 and upregulation of excitatory amino acid transporter 2 expression suggesting that glutamate was normally rapidly cleared from the synaptic cleft during acute ciguatera poisoning. However, neurotoxicity and reactive astrogliosis were not detected in the ACC after 7 days of P-CTX-1 exposure. The present results are the first characterization of P-CTX-1-invoked brain cortex neuronal excitotoxicity in vivo and supported the theme that neuron and astroglia signals might play roles in acute ciguatera poisoning.

Use of folk tests to detect ciguateric fish: a scientific evaluation of their effectiveness in Raivavae Island (Australes, French Polynesia).

Ciguatera fish poisoning is a seafood intoxication commonly afflicting island communities in the Pacific. These populations, which are strongly dependent on fish resources, have developed over centuries various strategies to decrease the risk of intoxication, including the use of folk tests to detect ciguateric fish. This study aims to evaluate the effectiveness of two folk tests commonly used in Raivavae Island (Australes, French Polynesia): the rigor mortis test (RMT) and the bleeding test (BT). A total of 107 fish were collected in Raivavae Lagoon, among which 80 were tested by five testers using the RMT versus 107 tested by four testers using BT. First, the performance between testers was compared. Second, the efficiency of these tests was compared with toxicity data obtained via the receptor binding assay (RBA) by assessing various parameter's values such as sensitivity (Se), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV). Comparisons of outcomes between folk tests and RBA analyses were considered: tests used separately or in a parallel versus the series approach by each tester. The overall efficiency of the RMT and BT tests was also evaluated when the judgments of all testers were "pooled". The results demonstrate that efficiencies varied between testers with one showing the best scores in detecting toxic fish: 55% with RMT and 69.2% with BT. BT gave the best results in detecting toxic fish as compared with RMT, giving also better agreement between testers. If high NPV and Se values were to be privileged, the data also suggest that the best way to limit cases of intoxication would be to use RMT and BT tests in a parallel approach. The use of traditional knowledge and a good knowledge of risky versus healthy fishing areas may help reduce the risk of intoxication among communities where ciguatera fish poisoning is highly prevalent.

Protective effect of Heliotropium foertherianum (Boraginaceae) folk remedy and its active compound, rosmarinic acid, against a Pacific ciguatoxin.

ETHNOPHARMACOLOGICAL RELEVANCE: Senescent leaves of Heliotropium foertherianum Diane & Hilger (Boraginaceae) are traditionally used in the Pacific region to treat Ciguatera Fish Poisoning. This plant contains rosmarinic acid that is known for its multiple biological activities. In the present study, H. foertherianum aqueous extract, rosmarinic acid and its derivatives were evaluated for their capacity to reduce the effect of ciguatoxins. MATERIALS AND METHODS: Aqueous extract of H. foertherianum leaves was prepared and studied for its effects against a Pacific ciguatoxin (P-CTX-1B) in the neuroblastoma cell assay and the receptor binding assay. Rosmarinic acid and six derivatives were also evaluated by means of these bioassays. For this purpose, we have developed an improved synthetic route for caffeic acid 3,4-dihydroxy-phenethyl ester (CADPE). RESULTS: Both the aqueous extract of H. foertherianum leaves and rosmarinic acid showed inhibitory activities against a Pacific ciguatoxin in the above bioassays. Among all the molecules that were evaluated, rosmarinic acid was the most active compound. CONCLUSION: These results confirm further the potential of H. foertherianum in the treatment of Ciguatera Fish Poisoning.

Hypnosis to alleviate the symptoms of ciguatera toxicity: a case study.

Ciguatera toxicity is a poisoning from consuming reef fish that had fed on dinoflagellates such as Gambierdiscus toxicus found along coral reefs. The toxin is oil soluble, odorless, colorless, tasteless, heat stable, and is concentrated in larger carnivorous fish such as amberjack, barracuda, eel, grouper, red snapper, sea bass, and Spanish mackerel. Onset of symptoms is usually within 6-12 hours after ingestion. Gastrointestinal symptoms lasting 1-2 days include abdominal pain, nausea, vomiting, and diarrhea. Neurological symptoms may persist for weeks or several months or--rarely--years and include circumoral and extremity paresthesias, temperature sensation reversal, itching, weakness, ataxia, and others. A patient with burning hands and feet who had not found relief using other methods had diagnosis of ciguatera toxicity assisted by hypnotically refreshed memory followed by rapid relief with hypnotic suggestions in 1 session and remained free of symptoms.

A review of traditional remedies of ciguatera fish poisoning in the Pacific.

Ciguatera fish poisoning (CFP) is an illness caused by eating tropical coral fish contaminated with ciguatoxins (CTXs). The clinical management of patients with CFP is generally supportive and symptomatic in nature as no antidote exists. Of the many drugs prescribed, several have been claimed to be efficient in small, uncontrolled studies, but the outcomes of treatments with these medicines are often contradictory. In New Caledonia, traditional remedies are commonly employed in the treatment of CFP and of the 90 plant species catalogued as useful in CFP, the most popular herbal remedy by far is a decoction prepared from the leaves of Heliotropium foertherianum Diane & Hilger (Boraginaceae). Other important plants used in the treatment of CFP include Euphorbia hirta L. (Euphorbiaceae) and Vitex L. sp. (Lamiaceae). This review focuses on the evidence for efficacy of these species and pharmacological studies which support their use. Other plants used in CFP and the conventional treatment of CFP are also discussed briefly.

Ability of certain plant extracts traditionally used to treat ciguatera fish poisoning to inhibit nitric oxide production in RAW 264.7 macrophages.

AIM OF THE STUDY: Ciguatera fish poisoning (CFP) is an intertropical ichthyosarcotoxism that manifests in complex assortment of symptoms in humans. Ciguatoxins (CTXs), issued from Gambierdicus spp., are causative agents of this intoxication. We have recently demonstrated that a Pacific CTX (P-CTX-1B) strongly modulated iNOS expression, leading to overproduction of nitric oxide (NO) in RAW 264.7 murine macrophage cells. NO produced in large amounts is involved in a wide range of pathophysiological processes. Many traditional remedies are commonly used in the Pacific against CFP. In this context, bioassay-guided screening was carried out to study NO inhibiting capacity of 28 selected plant extracts. MATERIALS AND METHODS: We prepared aqueous extracts of plants used in New Caledonia in the treatment of CFP and screened their NO inhibitory activity in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages. RESULTS: Among 28 plants tested, Euphorbia hirta (Euphorbiaceae), Syzygium malaccense (Myrtaceae), Schinus terebenthifolius (Anacardiaceae), Punica granatum (Punicaceae), Cerbera manghas (Apocynaceae), Vitex trifolia (Labiateae) and Ximenia americana (Olacaceae) showed inhibitory activity, validating their use as traditional remedies in CFP, and the potential for use in the treatment of conditions accompanied by NO overproduction. CONCLUSION: These plants are promising candidates for further screening of their active compounds through activity-guided fractionation.

Ciguatera risk assessment in two toxic sites of French Polynesia using the receptor-binding assay.

Ciguatera Fish Poisoning (CFP) is a tropical syndrome well known in remote archipelagos where the population is still dependent on fish resources. In order to assess the ciguatera risk in two islands of French Polynesia, Tubuai (Australes) and Nuku Hiva (Marquesas), a study was carried out on both Gambierdiscus populations as well as on various fish species using the receptor-binding assay (RBA) to detect and quantify ciguatoxins. Relationship between RBA data and size or weight of fish was evaluated, and when only few individuals for a particular species were available the trophic level was used to help comparisons between studied areas. According to epidemiological data, toxic versus safe areas were explored and compared in both islands. In Tubuai Island, Gambierdiscus cells were surprisingly absent in the north area, considered as a toxic area, but almost 94% of fishes were classified as RBA+. In contrast, the south area, supposed to be safe, was evolving to be a risky area because of the presence of Gambierdiscus cells and 74% of fishes being RBA+. In Nuku Hiva Island, Gambierdiscus cells were present in the toxic areas, Anaho, Taiohae and Taipivei, with two toxic blooms in Anaho Bay, but none in Terre Déserte, the fishing area of this island. With RBA data, fishes were analyzed to be RBA+ at a high percentage in Anaho and Taiohae, higher than in Taipivei and Terre Déserte areas. In general, our findings were congruent with epidemiological data and the knowledge of local people only for risky fish species.

Poisoning, envenomation, and trauma from marine creatures.

In the course of their clinical work or during leisure activity, family physicians occasionally may encounter patients with injuries from marine creatures. Poisoning, envenomation, and direct trauma are all possible in the marine environment. Ciguatera poisoning can result from ingestion of predatory fish that have accumulated biotoxins. Symptoms can be gastrointestinal or neurologic, or mixed. Management is mostly symptomatic. Scombroid poisoning results from ingestion of fish in which histamine-like substances have developed because of improper refrigeration. Gastrointestinal and systemic symptoms occur. Treatment is based on antihistamines. Envenomations from jellyfish in U.S. waters and the Caribbean are painful but rarely deadly. Household vinegar deactivates the nematocysts, and manual removal of tentacles is important. Treatment is symptomatic. Heat immersion may help with the pain. Stingrays cause localized damage and a typically severe envenomation. The venom is deactivated by heat. The stingray spine, including the venom gland, typically is difficult to remove from the victim, and radiographs may be necessary to localize the spine or fragment. Surgical débridement occasionally is needed. Direct trauma can result from contact with marine creatures. Hemorrhage and tissue damage occasionally are severe. Infections with organisms unique to the marine environment are possible; antibiotic choices are based on location and type of injury. Shark attacks, although rare, require immediate attention.

Seasonality of diarrhetic shellfish poisoning at a coastal lagoon in Portugal: rainfall patterns and folk wisdom.

Of the three types of toxicity known so far in Portuguese shellfish, only diarrhetic shellfish poisoning (DSP) and amnesic shellfish poisoning (ASP) are produced by microalgae that seem to have been present in the last decades or centuries. The most important paralytic shellfish poisoning (PSP) producer, Gymnodinium catenatum, is hypothesised to have been introduced quite recently as only in 1976 PSP toxicity was detected for the first time in shellfish from Galicia, NW Iberian Peninsula. While ASP presents very short episodes of contamination, the concentration of DSP toxins in some years surpasses human safety values for much longer periods. It is traditionally stated that shellfish should be consumed in 'months with R' (September-April). A retrospective study of the maximum monthly DSP levels attained in mussels from a coastal lagoon-Ria de Aveiro-between 1994 and 2001, showed that the highest frequency of months with concentrations surpassing the safety level of 2 microg/g digestive glands were found in June-September, followed by May and October. These months correspond with the months of lowest historical average rainfall in the period 1941-1998. Oscillations in the rainfall pattern coincided with earliest (or latest) detection by HPLC of DSP toxins in mussel in the years studied. In a semi-closed lagunar environment prone to in situ growth of DSP-producer microalgae, like Dinophysis acuminata, rainfall affects river output, lowering salinity and disrupting water column stability that favours Dinophysis growth. The seasonality of DSP recurrence may be connected to the folk adage on safety of shellfish consumption, after many years of empirical observations by coastal populations of diarrhoea episodes in summertime.

The spectrum of poisonings in Hong Kong: an overview.

Poisoning is an important health problem in Hong Kong. In 1990 alone, 6500 patients were treated in Hong Kong hospitals and there were 245 deaths. Two hospital-based studies indicated that exposures to poisons were intentional in the majority (96%) of adult cases, with hypnotics/sedatives (34%), household products (16%) and analgesics (14%) being most often used. Apart from drugs and chemicals, accidental poisoning may occur after the ingestion of Chinese medicines or vegetables contaminated with methamidophos. The former may contain highly toxic aconitine or podophyllin, declared and undeclared western drugs such as phenylbutazone and aminopyrine, and heavy metals. It is important that there be a continuing effort to collect information on the factors leading to and the pattern of poisonings in Hong Kong and other Southeast Asian countries. This is particularly valuable for childhood poisoning so that appropriate preventive measures can be taken.

Metabolic and toxic peripheral neuropathies including diabetes.

Current literature on neuropathies caused by metabolic defects and exogenous toxins is reviewed. Recent work on the molecular basis of hereditary amyloidosis is initially considered followed by various aspects of diabetic neuropathy and then the effects of ciguatoxin and podophyllin on peripheral nerves.