Severe gross and microscopic lesions and other changes were found in adult aquatic birds and in embryos from Kesterson Reservoir (a portion of Kesterson National Wildlife Refuge), Merced County, Calif., during 1984. Adult birds from that area were emaciated, had subacute to extensive chronic hepatic lesions, and had excess fluid and fibrin in the peritoneal cavity. Biochemical changes in their livers included elevated glycogen and non-protein-bound sulfhydryl concentrations and glutathione peroxidase activity but lowered protein, total sulfhydryl, and protein-bound sulfhydryl concentrations. Congenital malformations observed grossly in embryos were often multiple and included anophthalmia, microphthalmia, abnormal beaks, amelia, micromelia, ectrodactyly, and hydrocephaly. Mean concentrations of selenium in livers (94.4 ppm, dry weight) and kidneys (96.6 ppm) of birds collected at the Kesterson ponds were about 10 times those found at a nearby control area (8.3 and 12.2 ppm). We conclude that selenium present in the agricultural drainage water supplied to the Kesterson ponds accumulated in the food chain of aquatic birds to toxic concentrations and caused the lesion and other changes observed.

and electron microscopy. It is now clear that the basal cell adenoma as described by Kleinsasser and Klein" and by Batsakis' represents but one histomorphological expression of a varied, yet limited potential. One of these variants, in contrast to the classic basal cell adenoma, is associated with intercellular hyalin and/or replicated basement membrane material and is termed, by us, a membranous adenoma. A striking feature of this lesion is its similarity to the dermal cylindroma of the skin. The presentation of a patient with co-existing dermal cylindromas, trichoepitheliomas and a membranous adenoma of the parotid afforded an opportunity to compare the histopathology, histochemistry, and ultrastructural features of analogous tumors of the skin and salivary gland. CASE REPORTA 70-year-old Caucasian man was admitted to the Ann Arbor Veterans Administration Hospital because of a mass in his left cheek present for three months. There was no pain or facial weakness. Since age 20 numerous dermal cylindromas and trichoepitheliomas had been excised from his face and A left superficial parotidectomy with preservation of the facial nerve was done. The bulk of the parotid tumor was present in the anterior portion of the superficial lobe superior to the parotid duct with extension into the accessory lobe. There was no connection with the skin. MATERIALS AND METHODSSpecimens from both the parotid and cutaneous tumors were fixed in 10% neutral buffered formalin and embedded in paraffin. Sections were stained with each of the following: hematoxylin and eosin, Masson's trichrome and Movat's pentachrome.Acid and neutral mucosubstances were studied using Alcian Blue (pH 2.5, 0.4), mucicarmine, colloidal iron, and PAS with and without diastase, hyaluronidase, and sialidase (neuraminidase) digestion. Normal human submandibular gland was used as control tissue for sialomucins.Portions of both tumors immediately after removal were flash frozen in isopentane chilled in liquid nitrogen. Specimens were stored at -7OOC until sectioned in a cryostat at -1 5°C . The histochemical demonstrations on coverslips were done according to standard controlled methods for isocitric dehydrogenase, glucose 6-phosphate dehydrogenase, adenosine triphosphatase (pH 9.4), beta glucosaminidase 2460

We report an outbreak of thyrotoxicosis without true hyperthyroidism that occurred between April 1984 and August 1985 among residents of southwestern Minnesota and adjacent areas of South Dakota and Iowa. One hundred twenty-one cases were identified through surveillance of medical clinics, laboratories, hospitals, and physicians' offices. Investigation of the outbreak demonstrated an association between the occurrence of thyrotoxicosis and the consumption of ground beef prepared from neck trimmings processed by a single slaughtering plant (odds ratio, 19.0; P = 0.0001). The cause was confirmed by the findings of bovine thyroid tissue in samples of these trimmings and high concentrations of thyroid hormone in implicated samples of ground beef and the demonstration of prompt increases in serum thyroid hormone concentrations in volunteers who ate the implicated ground beef. Bovine thyroid tissue had been introduced into the neck trimmings inadvertently during the process of "gullet trimming," a procedure that harvests muscles from the bovine larynx. The outbreak resolved after this procedure was discontinued at the plant. The clinical features of the illness suggested the diagnosis of silent thyroiditis, and it is possible that sporadic cases--or even outbreaks--of thyrotoxicosis factitia caused by this mechanism may have occurred in the past but were not recognized.

Forty-four neoplasms were found at necropsy in 115 gerbils from a colony of wild-caught, and first- or second-generation laboratory-raised gerbils. Ten species of gerbils varying from 24 to 61 months of age were affected. The neoplasms occurred in 18 primary locations and included nine neoplasms previously unreported in gerbils. Unusual neoplasms included several squamous cell carcinomas of middle ear, squamous cell carcinoma of ventral marking gland, and Hodgkin's-like lymphoma. Neoplasms were a significant cause of morbidity and mortality in these aging animals.