Creation of synthetic homogeneous neighbourhoods using zone design algorithms to explore relationships between asthma and deprivation in Strasbourg, France

The concept of 'neighbourhood' as a unit of analysis has received considerable research attention over the last decade. Many of these studies raise the question of the influence of local characteristics on variations in health and more recently, researchers have sought to understand how the neighbourhood can influence individual health through individual behaviour. Relatively few studies discuss the question of the borders and definition of a neighbourhood but we know that the results from health or population datasets are very sensitive to how zones are constructed - part of the Modifiable Areal Unit Problem (MAUP). In reality, we know that neighbourhoods are not constrained by artificial statistical boundaries, but rather exist as complex multi-dimensional living communities. This paper tries to better represent the reality on the ground of these communities to better inform studies of health. In this work, we have developed an experimental approach for the automated design of neighbourhoods using a small tessellated cell as a basic building block. Using the software AZTool, we considered population, shape and homogeneity constraints to develop a highly innovative approach to zone construction. The paper reports the challenges and compromises involved in building these new synthetic neighbourhoods. We provide a fully worked example of how our new synthetic homogeneous zones perform using data from Strasbourg, France. We examine data on Asthma reported through calls to the emergency services, and compare these rates with an index of multiple deprivation (NDI) which we have constructed and reported elsewhere. Higher correlations between Asthma and NDI were found using our newly constructed synthetic zones than using the existing French census areas of similar size. The significance of our work is that we show that careful construction of neighbourhoods - which we claim are more realistic than census areas - can greatly aid unpacking our understanding of neighbourhood relationships between health and the social and physical environments.

Characterization of particles emitted by incense burning in an experimental house

The potential health effects of fine and ultrafine particles are of increasing concern. A better understanding of particle characteristics and dispersion behavior is needed. This study aims at characterizing spatial and temporal variations in fine and ultrafine particle dispersion after emission from a model source in an experimental house. Particles emitted by an incense stick burning for 15 min were characterized. Number concentration, specific surface area and mass were measured. Partial chemical analysis of particles was also realized. Near the burning incense stick, the maximum concentration was 25,500 particles/cm(3); the indoor PM(2.5) concentration reached 197 microg/m(3), and the specific surface area concentration was 180 microm(2)/cm(3). The estimated incense smoke density was 1.1 g/cm(3). Time of Flight Aerosol Mass Spectrometer measurements indicated that the organic fraction was predominant in the aerosol mass detected, and other minor components identified were K(+), NO(3)(-), and Cl(-). The combustion of an incense stick in the living room was associated with significant modifications of the concentrations of particles measured in the different rooms of the house. This demonstration of pollution by particle dispersion by a model source of moderate intensity may have significant implications in terms of assessment of indoor exposure to such particles. Practical Implications The particles emitted in a domestic environment by a source of moderate intensity such as burning incense disperse throughout the house, even in rooms with closed doors and in rooms as far away as the next floor. This dispersion has significant implications in terms of evaluating human indoor exposure to fine and ultrafine particles.

Asthma attacks and deprivation: gradients in use of mobile emergency medical services

BACKGROUND

To test whether rates of emergency telephone calls for asthma attacks are associated with contextual socioeconomic deprivation in the Strasbourg metropolitan area (France).

METHODS

Two mobile emergency medical service networks provided all data for 2000-2005 about emergency calls for asthma attacks, georeferenced by census block. Contextual deprivation was measured for each census block by a composite index, constructed by principal component analysis. Emergency call rates were calculated for each census block and for different age groups. Empirical Bayesian smoothing was used to reduce the instability of outlying rates.

RESULTS

Positive spatial autocorrelation was detected in both the health and the socioeconomic datasets. In all age groups, rates of calls for asthma attacks increased linearly with deprivation. Correlation coefficients between these two factors varied according to age group: 0.53 for the group aged 0-9 years, 0.46 for 10-19 years, 0.65 for 20-39 years, 0.70 for 40-64 years, 0.68 for 65 and older, and 0.77 for the age-standardised incidence ratio. These correlation coefficients were highly significant (p<0.01), even after spatial autocorrelation was taken into account.

CONCLUSION

The socioeconomic gradients observed are consistent with those observed for severe forms of asthma and asthma hospitalisations in Western countries.

External radiation exposure and mortality in a cohort of French nuclear workers

OBJECTIVE

To analyse the effect of external radiation exposure on the mortality of French nuclear workers.

METHODS

A cohort of 29 204 workers employed between 1950 and 1994 at the French Atomic Energy Commission (Commissariat à l'Energie Atomique (CEA)) or at the General Company of Nuclear Fuel (COmpagnie GEnérale des MAtières nucléaires (Cogema, now Areva NC)) was followed up for an average of 17.8 years. Standardised mortality ratios (SMRs) were computed with reference to French mortality rates. Dose-effect relationship were analysed through trend tests and Poisson regression, with linear and log-linear models.

RESULTS

The mean exposure to X and gamma radiation was 8.3 mSv (16.9 mSv for exposed worker population). A total of 1842 deaths occurred between 1968 and 1994. A healthy worker effect was observed, the number of deaths in the cohort being 59% of the number expected from national mortality statistics. Among the 21 main cancer sites studied, a statistically significant excess was observed only for skin melanoma, and an excess of borderline statistical significance was observed for multiple myeloma. A dose-effect relationship was observed for leukaemia after exclusion of chronic lymphoid leukaemia (CLL). The relative risk observed for non-CLL leukaemia, n = 20, was 4.1 per 100 mSv (90% CI 1.4 to 12.2), linear model and 2.2 per 100 mSv (90% CI 1.2 to 3.3), log-linear model. Significant dose-effect relationship were also observed for causes of deaths associated with alcohol consumption: mouth and pharynx cancer, cirrhosis and alcoholic psychosis and external causes of death.

CONCLUSION

The risk of leukaemia increases with increasing exposure to external radiation; this is consistent with published results on other nuclear workers cohorts.

Risk analysis of leukaemia incidence among people living along the Techa River: a nested case-control study

Large quantities of radioactive materials released over time from the Mayak nuclear weapons facility caused significant internal and external exposure for people living along the banks of the Techa River (Southern Urals, Russia). We conducted a nested case-control study in the Extended Techa River Cohort to determine whether the risk of leukaemia incidence increased with protracted exposure to ionising radiation or with other non-radiation risk factors. The study included 83 cases identified over 47 years of follow-up and 415 controls matched for sex, age at diagnosis, age (within a 5 year age group), and date of initial residence in the riverside area. External and internal doses have been calculated using the Techa River Dosimetry System 1996 (TRDS96). Conditional logistic regression was used to calculate odds ratios per Gray (OR/Gy) and 95% confidence intervals (95% CI). After excluding cases of chronic lymphoid leukaemia, the OR/Gy of total, external, and internal doses were 4.6 (95% CI: 1.7-12.3), 7.2 (95%CI: 1.7-30.0) and 5.4 (95%CI: 1.1-27.2), respectively. A history of solid tumour, either malignant or benign, before the leukaemia diagnosis was associated with a 2.5-fold increase in the leukaemia risk (95% CI: 1.1-5.9). Even though the analysis of confounders was less useful than expected because of missing data, multivariate analyses that took the exposure dose into account confirmed the association between leukaemia incidence and tumour history.

Public health benefits of compliance with current E.U. emissions standards for municipal waste incinerators: a health risk assessment with the CalTox multimedia exposure model

The Angers municipal solid waste incineration plant, in operation since 1974, was upgraded in 2000 to comply with new European standards. This article discusses the risks associated with past and present emissions from the incinerator and its nearby furnace. Emissions of SO(2), HCl, particulate matter, lead, mercury, cadmium and dioxins were studied. We characterised the risks associated with exposure via inhalation and ingestion of locally grown products, before and after the upgrade. Emissions were estimated from regulatory measurements, and ambient air concentrations estimated with a Gaussian dispersion model. The CalTox multimedia model was used to calculate concentrations in the food chain. Food intake rates came from a nationwide survey. Inhalation exposure to respiratory irritants produced a hazard ratio less than 1 in all scenarios, except for SO(2) in the immediate neighbourhood of the incinerator, before the change in furnace fuel and in case of high-pressure weather conditions. The individual excess risk of cancer was less than 10(-6) and the hazard ratios for metals were less than 1. Before compliance, the average dioxin exposure attributable to the incinerator accounted for roughly one quarter of the average total exposure from traffic and other combustion activities. Although the corresponding hazard ratio was less than 1, the individual lifetime excess risk, assuming no change in emissions, was 2 x 10(-4). After compliance, all hazard ratios and future individual lifetime excess risks appear minimal. These results are consistent with environmental data and other studies, but many uncertainties remain, such as intermedia transfer coefficients for dioxins. Nevertheless compliance has vastly reduced the probability of health effects.

[Is compliance to current lead regulations safe enough for infants and toddlers?]

BACKGROUND

Neurobehavioural and cognitive impairment may arise from children's exposure to lead. To prevent this risk, a Tolerable Daily Intake (TDI) has been issued by WHO and many regulations addressing lead emission to the environment have been introduced. Taking into account both lead concentrations in soil and the importance of soil in children's exposure, we examined whether compliance to the above current regulations is safe enough for children.

METHODS

Exposure scenarios were devised for infants and toddlers, the 2 populations most sensitive to lead toxicity, considering three typical environmental settings, that is, rural, urban, and in the vicinity of lead emitting industrial sites. For all 3 scenarios, we used available data describing the current French levels of both lead contamination in various media (water, air, soil) and lead intake through food. Acute lead intoxication from old lead-containing paints was excluded from this study.

RESULTS

We have shown that WHO's TDI is exceeded in several situations for both populations, and thus children may be subject to unacceptable levels of risk.

CONCLUSION

We conclude that it may be advisable to take fuller account of the contribution of soil to lead exposure.

[Radon exposure and risks for public health]

Radon is a radioactive gas of natural origin. Its principal isotope is radon-222, stemming from uranium-238 present at various concentrations in all soils. Radon is found everywhere in the earth's atmosphere but has low reactivity by itself. Radon particulate daughters are however responsible for alpha irradiation of the bronchial epithelium. Epidemiologic studies on miners have shown long ago that radon exposure causes an increased risk of lung cancer in these workers. More recently, its risk associated with radon exposure was addressed in public dwellings. It is generally agreed that the risk of lung cancer is plausible in this setting. In particular, radon exposure in some dwellings may be comparable to that undergone by several uranium miner populations. However, simple and low-cost steps can be taken to significantly reduce radon exposure in dwellings.

Microscopic identification of asbestos fibres associated with African clay crafts manufacture

The use of asbestos in manufacturing is a world-wide phenomenon, not just confined to the developed world. The activity described below shows that there are similar problems in the third world which need to be tackled. A sample of white fibrous material used in pot making by women in a village of Botswana was provided for analysis. The identification of fibres was carried out using established analytical and vibrational microspectroscopic methods. The occupational hygiene implications and the measures which may need to be taken in order to improve the safety of the pot making process are discussed in this article.

[Evaluation of the psychological consequences of environmental catastrophes: a feasibility study based on the 1992 floods in the Vaucluse]

Scientific studies of environmental disasters, whether human or natural in origin, have shown that the psychological impact of such events may be considerable and long-lasting. Several natural disasters have occurred in France, but their impact on public psychological health has not been assessed. In September 1992, there was a major flood in southeast France (Vaucluse), which caused 38 deaths. Four years later, we performed a pilot cross-sectional study to assess the feasibility of a larger epidemiological study to assess the psychological impact of this flood. Two affected towns were chosen for this study: Vaison-la-Romaine (VLR), where the flood was very sudden and 29 people were killed, and Bédarrides, where the water level rose more slowly. In Bédarrides, households were randomly selected from a list of victims (n = 100) and in Vaison-la-Romaine, households were randomly selected from the telephone directory (n = 140). Exposure to the flood was assessed by a series of questions, the answers to which were used to calculate an exposure score. The questionnaire also included psychometric scales for post-traumatic stress disorder (QE-PTSD), anxiety (Spielberger State-Trait Anxiety Inventory) and depression (Beck Depression Inventory). In Bédarrides, the participation rate was high: 69% of the selected households were successfully contacted and found to be eligible for inclusion and 74% agreed to a face-to-face interview. In Vaison-la-Romaine, 51% of the selected households were contacted and eligible and 50% agreed to the face-to-face interview. Our survey showed that exposure was multidimensional and that it was possible to calculate an exposure score suitable for the analysis of exposure-effect relationships. The PTSD scale was completed well by the interviewees, several of whom did not fill in the depression and anxiety scales correctly. However, analysis of the responses obtained showed that these tools had a high level of internal consistency. Cross-correlations between the various psychological scales used in this study were highly significant (p < 10-4). There was some degree of association between some psychometric scales and exposure. This pilot study shows that a cross-sectional study of the long-term psychological consequences of an environmental disaster could be carried out several years after the event but that the feasibility of such a study depends ultimately on its acceptance by the public and the relevant authorities. It underlines the need to collect exposure data immediately after the event and enabled us to identify and to adapt the tools required for this kind of evaluation. It should encourage public health decision-makers to support such evaluation and to improve the psychological and social support available to people exposed to floods.

Agent orange and the risk of gestational trophoblastic disease in Vietnam

There have been claims of an increased risk for gestational trophoblastic disease (i.e., hydatidiform mole and choriocarcinoma) in Vietnam since the period of Agent Orange sprayings. In 1990, we conducted a case-control study in Ho Chi Minh City to investigate risk factors for gestational trophoblastic disease in Vietnam. Eighty-seven married women, all of whom had a recent pathologic diagnosis of gestational trophoblastic disease, identified in the Obstetrical and Gynecological Hospital, were included in the study. Eighty-seven married women who were admitted mainly in the surgery departments of the same hospital were the controls, and they were matched to cases for age and area of residence. Odds ratios (ORs), adjusted for matching variables and other potential confounders, were estimated with unconditional logistic regression. A statistically significant trend in risk was observed with previous live births (p = .01). Cases were found to eat less meat per wk (OR = 0.4, 95% confidence interval [95% CI] = 0.2-0.9 for > or = five meat dishes) and to own fewer consumer goods than controls. An increase in risk was associated with the breeding of pigs (OR = 5.7, 95% CI = 1.2-27.6 for raising three or more pigs). A cumulative Agent Orange exposure index was constructed, using the patient's complete residence history. No significant difference was found between cases and controls for this index (OR = 0.7, 95% CI = 0.2-1.8 for high-exposure category), nor was such a difference noted for the agricultural use of pesticides.

Stability of therapeutic drug measurement in specimens collected in VACUTAINER plastic blood-collection tubes

Recently Becton-Dickinson marketed a plastic serum-separator tube that uses the same serum-separator gel as the glass tubes. We studied the stability of therapeutic drugs stored in plastic tubes by comparing it with the stability of drugs stored in glass serum-separator tubes and plain red-top glass tubes. We observed no absorption of caffeine, primidone, N-acetylprocainamide, procainamide, theophylline, tobramycin, ethosuximide, acetaminophen, amikacin, valproic acid, methotrexate, salicylate, and cyclosporine in either plastic or glass serum-separator tubes. On the other hand, concentrations of lidocaine, quinidine, phenobarbital, and phenytoin were reduced after storing in both plastic and glass serum-separator tubes, especially with prolonged storage and small sample volume. The reduction in concentrations were due to slow absorption of those drugs by serum-separator gel.

Effect of heating sera under conditions necessary for deactivation of human immunodeficiency virus on commonly monitored therapeutic drugs

Minimizing the risk of infection of laboratory staff from contaminated blood samples is a major safety goal in a clinical laboratory. One dangerous pathogen, the human immunodeficiency virus (HIV) can be deactivated by heating sera at 56 degrees C for 30 min. We studied the effect of such heat treatment on serum concentrations of 11 commonly monitored therapeutic drugs. We used blood specimens collected in serum separator tubes (SSTs), which were routinely submitted for therapeutic drug monitoring in our laboratory for this study. Concentrations of digoxin in sera were measured using a fluorescence polarization immunoassay (FPIA), while concentrations of tobramycin, gentamicin, vancomycin, theophylline, valproic acid, procainamide, N-acetylprocainamide (NAPA), phenytoin, phenobarbital, and carbamazepine were measured by enzyme-multiplied immunoassay technique assays using a Monarch 2000 analyzer. We observed no significant change in the concentration of any drug except phenytoin and carbamazepine following heating at 60 degrees C. The decrease in concentration of phenytoin and carbamazepine after heating was related to absorption of the drug to the gel rather than the instability of the drug under heating conditions. We conclude that blood contaminated with HIV may be deactivated by heating prior to analysis for most of the routinely monitored therapeutic drugs.

Correlation between dioxin levels in adipose tissue and estimated exposure to Agent Orange in south Vietnamese residents

To permit new epidemiologic studies of the effects of dioxin on humans in Vietnam, we evaluated a model for quantifying exposure to Agent Orange (exposure index) based on the residential histories of 27 Vietnamese subjects and on information about spraying from the U.S. Army records (Herbs Tape) and compared this index to the dioxin levels measured in the subjects' adipose tissue. The mean dioxin level was 7.8 ppt, and dioxin and furan isomer profiles were similar to those already reported in industrialized countries. In addition, there was a highly significant correlation between the levels of almost all the isomers, whatever their degree of chlorination. For the group of 27 subjects, we found a Pearson correlation coefficient of 0.36 (P = 0.07) between the dioxin levels and the exposure index after log-transformation of both variables. When the analysis was restricted to the 22 subjects with a positive exposure index, the Pearson correlation coefficient rose to 0.50 (P = 0.02). We conclude that despite the limitations and power conditions of the study, this result is encouraging because it will be useful for future epidemiologic studies in Vietnam.

Viral infections and chemical exposures as risk factors for hepatocellular carcinoma in Vietnam

A case-control study investigating risk factors for hepatocellular carcinoma (HCC) was conducted in Hanoi, in the north of Vietnam, between 1989 and 1992. Male cases of HCC (152) diagnosed in 2 hospitals were included. Hospital controls (241) admitted mainly to abdominal surgery departments were frequency-matched to cases for sex, age, hospital and place of residence (Hanoi, province). Odds ratios adjusted for matching variables and other potential confounders were estimated using unconditional logistic regression, or exact non-parametric statistical inference when numbers were small. Positivity for hepatitis B surface antigen (HBsAg) was the main risk factor for HCC in this sample. Five subjects (3 cases, 2 controls) had been infected by hepatitis C virus (HCV), and none of them were carriers of HBsAg, giving an OR of 38 associated with HCV infection among HBsAG-negative subjects. Alcohol drinking was associated with HCC and interacted with HBsAg positivity. Agricultural use of organophosphorous pesticides (30 liters/year or more) and military service in the south of Vietnam for 10 years or more were also associated with an increased risk of HCC. This study confirms the major role played by HBV infection and its association with HCC in south-east Asia. It also suggests how other factors such as alcohol consumption or exposure to chemicals may interact with HBV infection.

Massive overfeeding and energy balance in men: the Guru Walla model

To determine the magnitude of the thermogenic response to a massive long-term overfeeding, an energy-balance study was carried out in nine lean, young Cameroonian men participating in a traditional fattening session: the Guru Walla. Food intake, body weight, body composition, activity, and metabolic rates were recorded during a 10-d baseline period and over the 61-65 d of fattening. Total energy expenditure (TEE) was measured by using doubly labeled water during the baseline period and the final 10 d of Guru Walla. Cumulative overfeeding consisted of 955 +/- 252 MJ (chi +/- SD) mainly as carbohydrate. Body-weight increase was 17 +/- 4 kg, 64-75% as fat. Metabolic rates increased but TEE did not. However, when accounting for the reduction in physical activity, substantial thermogenesis was observed but its amplitude was not greater than that observed under less extreme carbohydrate-overfeeding conditions. If luxuskonsumption does exist, it is not related to the magnitude of the cumulative overfeeding.

Expression and activity of gamma-glutamyl transpeptidase in the rat epididymis

Following Northern analysis, GGT mRNA was found predominantly within the caput epididymides and kidney. The size of mRNAs for kidney, caput, corpus, and ductus deferens were 2.2, 2.3, 2.2, and 2.3 kb, respectively, whereas cauda showed a doublet of 2.2 and 2.3 kb. GGT transpeptidation and hydrolytic activity within epididymal luminal fluids collected by micropuncture showed caput = corpus greater than cauda and corpus greater than caput greater than cauda, respectively. Caput luminal GGT transpeptidation activity was significantly inhibited by serine-borate and was optimal at pH 8.0. The calculated Km and Vmax values for hydrolysis of GSH by caput luminal GGT were 0.06 microM and 2.19 nmoles/min/microliters luminal fluid at pH 8.5 compared to 0.49 microM and 0.49 nmoles/min/microliters luminal fluid, respectively, at the physiological pH 6.5 of caput fluid. These studies would suggest that the epididymis can control the activity of luminal GGT by pH. Lower Km (0.12 microM) and higher Vmax (1.13 nmoles/min/microliters luminal fluid) values were also calculated when GSSG was used compared to GSH. Results from Triton X-114 partitioning experiments suggest that luminal GGT probably exists in both membrane bound and nonmembrane bound forms. Western blot analysis of proteins within epididymal luminal fluids revealed both subunits of GGT in all epididymal regions studied. However, two lower molecular bands, approximately 22 kDa and 21 kDa, were also observed in cauda fluid. It is suggested that as GGT is transported along the epididymal duct it undergoes degradation, which accounts for its loss of activity in the distal epididymal regions.(ABSTRACT TRUNCATED AT 250 WORDS)

Clearance of proteoglycan from joint cavities

The rate of loss from the synovial cavity of proteoglycan subunit, a major constituent of cartilage, has been measured in rabbits with and without experimental arthritis. The effect of aggregation between proteoglycan and hyaluronic acid upon the rate of elimination has also been investigated. The results indicate that proteoglycan subunit has a clearance half life of around 12 hours in normal joints and that this rate is not significantly altered in the presence of an active synovitis. Neither injection of proteoglycan as an aggregate, nor in a form incapable of aggregation, had any significant effect on clearance rates. These data indicate that loss of proteoglycan from the joint is not retarded by its ability to aggregate with hyaluronic acid in the synovial fluid and, together with measurements of synovial fluid proteoglycan, may enable rates of cartilage breakdown in vivo to be calculated.

Effects of a moderate dietary fibre supplement on hunger rating, energy input and faecal energy output in young, healthy volunteers. A randomized, double-blind, cross-over trial

The effects of moderate dietary-fibre supplementation on satiety, energy intake and faecal energy excretion were studied in 20 young healthy volunteers of normal body weight, mean body mass index 20.9, receiving a dietary fibre supplement of 7.3 g per day in a randomized, double-blind, cross-over study. Hunger feeling, energy intake, and defaecation pattern, were recorded daily during a 2-week control period and then, during two 4-week treatment periods. Furthermore, faecal energy output was determined during the last week of each treatment period. The fibre treatment, as compared to placebo, resulted in a significantly higher faecal energy excretion: 173 kcal/d (163-183 kcal/d) vs 153 kcal/d (135-171 kcal/d), respectively (P less than 0.05); a decrease in hunger rating (using a visual analogue scale) (P less than 0.05); an increase in number of bowel movements (P less than 0.05), and a softer consistency of the stools (P less than 0.05). There was no significant difference in mean energy intake between the two treatment periods. This study demonstrated that moderate dietary fibre supplementation in normal man increases faecal energy excretion with simultaneously decreased hunger feeling. These beneficial effects may have therapeutic value in the management of obesity.

[Study of the iron status of a population of pregnant women]

Serum ferritin, haemoglobin, erythrocyte constants, serum iron and the fixation capacity of transferrin were determined in 233 pregnant women consulting a maternity clinic in the Paris area. 1 metropolitan frenchwoman out of 9 and almost half of the immigrants were found to suffer from anaemia at term. A virtual absence of iron reserves (serum ferritin less than microgram/l) was found in 20% of the metropolitan women during the 3rd month of pregnancy, in 60% during the 6th month and in 75% during the 9th month. The figures were 60%, 100% and 90% respectively in the immigrant group. Considering the anaemia-related risks and the eventual repercussions of iron deficiency on a pregnancy, the health of the mother and the foetus, a systematic increase in iron as of the 2nd trimester of pregnancy is recommended.

Acylation of endogenous phospholipids and added lysoderivatives by rat liver plasma membranes

Phospholipid acyltransferase activities of plasma membranes have been investigated with various acyl-CoA thioesters (palmitoyl, stearoyl, oleoyl, linoleoyl and arachidonoyl) with and without added lysoderivatives. Different patterns of incorporation were observed for each acyl-CoA into endogenous phosphatidylcholine and phosphatidylethanolamine. The turnover rates calculated with tracer amounts of 10 microM acyl-CoA thioesters were five times faster for the polyunsaturated than for the saturated acyl moieties of phosphatidylethanolamine and phosphatidylcholine. Arachidonoyl-CoA was the best acyl donor at low concentrations and the maximal turnover rate was observed at about 25 microM. No saturation appeared at up to 100 microM linoleoyl-CoA. Linoleoyl-CoA transacylase acylated the lyso-compounds in the following order: lysophosphatidylcholine greater than lysophosphatidylserine and lysophosphatidylinositol, while lysophosphatidylethanolamine inhibited linoleate incorporation into the phosphatidylethanolamine itself. Linoleoyl-CoA transacylation was not affected by the fatty acyl moiety at the 1-position of the lysophosphatidylcholine. The results support the view that the plasma membrane acyltransferase activity might contribute to the formation of bile phosphatidylcholines.