Improved effluent quality at a bleached kraft mill as determined by laboratory biotests.

A life-cycle experiment with fathead minnows and Ceriodaphnia survival/reproduction tests were used to evaluate the quality of the effluent from a bleached kraft mill after the implementation of various process modifications and effluent treatment changes. In the life-cycle experiment, the fish were exposed in the laboratory to well water (control) and five concentrations (1.25%, 2.5%, 5%, 10%, or 20%) of effluent from the egg stage to sexual maturity and reproduction (approximately 190 d). None of the effluent concentrations significantly affected the hatching of the eggs, the mortality, weight, length, gender balance, reproduction, and prevalence of visible morphological or histopathological abnormalities of the hatched fish, and the hatchability of the first generation eggs. In Ceriodaphnia tests, the IC25 of the effluent affecting reproduction was approximately 80%. This threshold concentration is well above the 0.7% average yearly concentration of the effluent that exists in the recipient near the point of discharge. The results of these biotests were compared to the results of the same biotests conducted earlier with the effluent from the mill prior to process and treatment modifications. The comparison indicated that since the earlier work, the quality of the mill's effluent improved substantially. Threshold concentrations affecting fathead minnows in the life-cycle experiment and the Ceriodaphnia tests increased by more than eightfold and approximately twofold, respectively. While the most important change in the mill operating conditions responsible for the improvement could not be identified, these results indicate that mills can undertake process and treatment modifications that result in the discharge of effluents seemingly compatible with the aquatic environment.

The effects of a secondary-treated bleached kraft mill effluent on aquatic organisms as assessed by short-term and long-term laboratory tests.

The chronic effects of secondary-treated effluent from a bleached kraft mill were assessed by means of long-term and short-term laboratory tests. In the long-term test, the effects of the effluent on the life cycle of fathead minnows (Pimephales promelas) were studied. In this experiment, which began with the egg stage and continued through to sexual maturity and reproduction, the fish were exposed in the laboratory to well water (control) and five concentrations (viz., 1.25, 2.5, 5, 10, or 20%) of effluent for 275 days. The effluent concentrations did not significantly affect the hatching of the eggs, the mortality of the hatched fish, the incidence of visible morphological abnormalities, the mortality and the hatchability of the first generation eggs and larvae, and the weights of minnows at various stages of development. Based on a conservative evaluation of the data, a significant finding of this work was that effluent concentrations > or = 2.5% caused lower egg production as well as changes in the gender balance (i.e., increased numbers of individuals with male secondary sexual characteristics) of the fish. Further work is required to understand the causes and ecological significance of these findings. Two short-term tests, each lasting 7 days, were also run. In one, even 100% effluent did not reduce the survival or growth of minnow larvae, correctly predicting the lack of effluent effects on similar endpoints in the long-term test. In the other short-term test, while the survival of Ceriodaphnia was also unaffected by 100% effluent, their reproductive capacity was reduced, but only at effluent concentrations an order of magnitude greater than those affecting the reproduction of minnows in the long-term test.

Effects of a secondary-treated thermomechanical pulp mill effluent on aquatic organisms as assessed by short- and long-term laboratory tests.

The chronic effects of secondary-treated effluent from a thermomechanical pulp (TMP) mill were assessed by means of long-term and short-term laboratory toxicity tests. The effluent used for the tests was sampled at a western Canadian mill using mostly softwoods and < 10% recycled fiber as furnish. In the long-term test, the effects of the effluent on the life cycle of fathead minnows (Pimephales promelas) were studied. In this experiment, which began with the egg stage and continued through to sexual maturity and reproduction, the fish were exposed in the laboratory to well water (control) and five concentrations (1.25%, 2.5%, 5%, 10%, or 20%) of effluent for 202 d. None of the effluent concentrations significantly affected the hatching of the eggs, the mortality, weight, length, gonad size, gender balance, and reproduction of the hatched fish, the prevalence of gross morphological and histopathological changes, and the hatchability of the first generation eggs. Two short-term tests, each lasting 7 d, were also performed. In these tests, 100% effluent caused no change in the survival/growth of minnow larvae or in the survival/reproduction of Ceriodaphnia.

Quality of life for 'new' long-stay psychiatric in-patients. The effects of moving to a hostel.

We observed 15 'new' long-stay patients in wards in a District General Hospital Unit and a mental hospital, and again when they had lived for a year in a new hospital-hostel. There were significant changes in time spent in the community, social interaction, activity and abnormal behaviour. Residents believed they had more freedom and none wanted to return to wards. Six patients remained on wards. They showed no comparable changes and all wanted to live elsewhere.

Care of "new" long-stay patients in a district general hospital psychiatric unit. The first two years of a hospital-hostel.

The paper describes the need for long-term inpatient care in an English health district whose psychiatric services were based on a unit in a District General Hospital. Patients who became long-stay were placed in a new hospital-hostel in a city centre. Three quarters of those eligible could be managed in the hostel, with those rejected posing more control problems. Patients in the hostel became less withdrawn and increased their activity and use of community facilities.

Estimating suicide risk among attempted suicides. II. Efficiency of predictive scales after the attempt.

We predicted that the closer the resemblance of attempted suicide to completed suicide, the greater the risk of patients later killing themselves after an unsuccessful attempt. Using two risk scales, one of 6 and the other of 18 socio-demographic and clinical items, weighted according to their value in discriminating between suicides and attempted suicides, and a rating of intent to die during the index suicide attempt, we followed up 1263 attempted suicides for two years. Ten of the twelve suicidal deaths in the first year occurred in patients scoring in the top quartile on the 6-item scale; and among high-risk scorers there was an excess of those defined as 'failed suicides' at the index attempt. The 18-item scale was superior to the shorter one, but both scales were improved by taking into account the rating of intent-to-die. The potential value of these findings is discussed in the light of some inherent problems of predicting suicide in the clinical setting.

Schizophrenic patients and their families. A survey in a psychiatric service based on a DGH unit.

We identified the population of schizophrenic patients under 65 in a geographically defined area. The number using psychiatric services based on a new District General Hospital unit in the course of one year was 364, a prevalence of 2.2 per 1000 adult population. Half the patients lived in supportive private households, most often with spouses or mothers. More women than men married and retained supporters. Patients and their primary supporters were interviewed separately. The PSE Catego programme classed 47 per cent of patients as psychotic. Supporters reported disturbed behavior in 65 per cent of patients, and restricted social performance in 78 per cent. There was evidence of hardship (emotional and physical ill-health, problems with children) in 90 per cent of households. Supporters' subjective distress was directly related to the presence of psychosis and disturbed behaviour and inversely related to the duration of the illness. Drop-out and failure to take medication appeared to be causes of the relatively high prevalence of psychosis.

Evaluation of a social work service for self-poisoning patients.

Four hundred patients aged at least 17 who came to Casualty in one year after deliberately poisoning themselves were randomly assigned between an Experimental social work service (task-centered casework) and a Control (routine) follow-up service. 139 patients were excluded from the trial, most of whom were already in continuing psychiatric treatment. After one year there was no difference in the proportions of E and C patients who repeated self-poisoning (about 14 per cent), but significantly more of the excluded group had repeated (36 per cent). A random half of the trial patients were re-interviewed four months after admission. Both E and C groups had improved to a significant extent on measures of depressed mood and of social problems. E patients showed more change in social problems and were more satisfied with the service they had received.