Psychological treatments for depression in pre-adolescent children (12 years and younger): systematic review and meta-analysis of randomised controlled trials.

The objective of this study was to evaluate the efficacy of psychological treatments for depression in pre-adolescent children, a disorder affecting 1-2 % of children in this age range. A systematic review of studies of psychological interventions to treat depressive disorder in pre-adolescent children (aged up to 12-years-old) was carried out. The primary outcome was level of depressive symptoms. Studies were found using Medline, PsycINFO, EMBASE and Web of Knowledge databases and selected on several criteria. Only randomised controlled trials were included. Where individual studies covered a broader age range (usually including adolescents up to age 18 years), authors of those studies were contacted and requested to provide individual patient level data for those aged 12 years and younger. 2822 abstracts were reviewed, and from these 124 full text articles were reviewed, yielding 7 studies for which we were able to access appropriate data for this review. 5 of these studies evaluated cognitive behaviour therapy (CBT). Combined results from these studies suggest that there is a lack of evidence that CBT is better than no treatment [standard mean difference -0.342 (95 % confidence interval -0.961, 0.278)], although the number of participants included in the trials was relatively small. The evidence for efficacy of family therapy and psychodynamic therapy is even more limited. The very limited number of participants in randomised controlled trials means that there is inconclusive evidence for the psychological treatment of depression in children aged 12 years and below. Given the prevalence and significant impact of this disorder, there is an urgent need to establish the effectiveness or otherwise of psychological intervention.

Stories of change: the text analysis of handovers in an Italian psychiatric residential care home.

WHAT IS KNOWN ON THE SUBJECT?: There is a growing emphasis on communication as a result of the move towards the more inclusive approach associated with the community-based rehabilitation model. Therefore, more importance is attached to handovers. Besides ensuring transfer of information, handovers enhance group cohesion, socialize staff members to the practices of the service and capture its organizational culture. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: While handovers are mainly used for information transfer and to manage the services' daily routine, this paper offers an insight on how handovers can be conceived as valuable instruments to document cultural and organizational change. Only a limited amount of studies has focused on handovers in mental healthcare settings, and most of them only consider the perspectives of psychiatric nurses, while embracing a broader perspective, this paper provides valuable insights into the perspectives of various service providers. The overcoming of the dichotomy deficit-based vs. recovery-oriented model is possible if professionals use handovers to reflect upon their practice and the ways in which their cultural models are affected by the environmental context. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Handovers are valuable instruments to document organizational change. It would be important for psychiatric and rehabilitation facilities to keep track of the handover records over time as they may provide insightful information about cultural change and the transformations in the core values and beliefs held by professionals. ABSTRACT: Handovers assure a timely and correct information transfer while socializing workers to the service's culture; however, no study describes them as instruments to document organizational change and only a few have focused on psychiatric settings. Aim To investigate the change in the culture of an Italian psychiatric residential care home as perceived by its mental health workers (MHWs) over the course of two decades. Method Emotional text analysis (ETA) was used to analyse the MHWs' handovers completed from 1990 to 2011. Results The analysis generated four clusters and three main factors illustrating the change in the MHWs' representations of the residential care home and its occupants. The factors showed: (1) the shift from an individualistic, problem-focused view to an inclusive, community-based approach; (2) the presence of a descriptive as well as a specialized language; and (3) the presence of a double focus: on patients and professionals. Conclusions Handovers transcripts document the following changes: (1) a shift from a symptom-based to a recovery-oriented approach; (2) a modification of the MHWs values towards an holistic view of the patient; (3) a growing importance assigned to accountability, services integration and teamwork. The paper shows that handovers can be used diachronically to document organizational change.

Psychiatric disorders in cases of completed suicide in a hospital area in Spain between 2007 and 2010.

INTRODUCTION: Suicide is an important Public Health problem. One of the most relevant known risk factors for suicide is suffering from a mental health disorder, identified in up to 90-95% of completed suicides, with this risk being increased if comorbidity is present. Findings from international research on the most common psychiatric disorders are dichotomous, divided into mood disorders and psychotic disorders. In Spain, data of this kind are scarce. METHODS: This study describes the psychiatric and forensic characteristics of completed suicide cases (n=79) ocurred in a psychiatric hospital healthcare area (in Spain), between 2007 and 2010. The forensic data were obtained from the Institute of Legal Medicine of Catalonia and the clinical data by reviewing the clinical records. RESULTS: Most of the subjects in this sample were males (78.5%, 95% CI; 68.4%-87.3%). Almost half of the sample (45.4%, 95% CI; 33.8%-57.1%, 35/77) had records in the Mental Health Services Network (including substance misuse services). Two of the 79 were under 18, so we were not able to access the records. More than half (54.3%, 95% CI; 37.1%-71.4%) of those with psychiatric history suffered from a mood disorder; 37.1% (95% CI; 22.9%-51.4% from a depressive disorder; 14.3% (95% CI; 2.9%-25.7%) from a bipolar disorder, and 17.1% (95% CI; 5.7%-31.4%) suffered from a psychotic disorder. With regard to substance misuse, 42.9% (95% CI; 25.7%-60.0%) presented substance misuse, and 48.6% did not. CONCLUSIONS: Psychiatric and forensic characteristics of completed suicide in this Spanish sample confirm previous findings from international studies: there is a high rate of psychiatric disorders in those who complete suicide, and there is a specific pattern as regards the method used to complete it.

[Assessment of exposure to organic aromatic compounds and PAH in asphalt industry: the PPTP-POPA Study results]. / Valutazione dell'esposizione a composti organici aromatici e IPA nelle opere di asfaltatura: i risultati dello Studio PPTP-POPA.

Asphalt is a mixture of mineral matter and bitumen, its fumes contain about 1% of Polycyclic Aromatic Hydrocarbons (PAH), some of which are carcinogens. In the PPTP-POPA Study of Lombardy Region, a group of 100 asphalt workers (exposed to bitumen fumes and diesel exhausts) and a group of 47 ground construction operators (exposed only to diesel exhausts) were investigated to assess PAH exposure in Italy, by means of environmental-air monitoring (the 16 most relevant, according to the American Environmental Protection Agency, EPA) and biological monitoring (urinary 1-hydroxypyrene excretion). Our results show that PAH exposure in these workers is not higher than that observed in traffic policemen working in urban areas. Since dermal exposure has been suggested as a major determinant of the total PAH dose absorbed by road pavers from bitumen fumes, we assessed skin contamination by organic aromatic compounds and by sixteen PAH: in both groups, six pads were applied to each subject in different parts of the body, during the workshift. The results show that the dermal contamination in road pavers is higher than in ground construction operators and that cutaneous dose rate is higher than respiratory dose rate, whereas the amount of absorption the ratio is inverted.

Una presentación no tan atípica: autismo en mujeres / Not an Atypical Presentation: Autism in Women

A pesar del conocimiento que tenemos en la actualidad de la amplia variedad de sintomatología y fenotipos de pacientes que engloban los Trastornos del Espectro Autista, algunos de estos fenotipos siguen sin estar claramente descritos en las clasificaciones psicopatológicas. Se propone un caso clínico de una paciente adolescente que consulta por sintomatología depresiva, descubriéndose tras la evaluación y durante la evolución un Trastorno del Espectro Autista subyacente que había pasado desapercibido

Despite current knowledge about the wide variety of symptoms and phenotypes of patients that meet criteria for Autism Spectrum Disorder, some of these phenotypes are still not clearly described in psychopathological classifications. A clinical case of a teenage patient who consults for depressive symptoms is proposed. After the evaluation, an underlying Autism Spectrum Disorder that had gone unnoticed was discovered

Determination of hexafluoroisopropanol, a sevoflurane urinary metabolite, by 9-fluorenylmethyl chloroformate derivatization.

A reversed-phase HPLC method with fluorescence detection for the quantification of hexafluoroisopropanol (HFIP) in urine is presented. HFIP, a metabolite of the inhalation anesthetic sevoflurane, is excreted mainly in urine as glucuronic acid conjugate. After enzymatic hydrolysis of the glucuronate, primary amino groups of interferent urinary compounds are blocked by reaction with o-phthalic dicarboxaldehyde and 3-mercaptopropionic acid, followed by labeling of HFIP with 9-fluorenylmethyl chloroformate. The derivatization reaction proceeds in a water-acetonitrile (1:1) solution at room temperature with a borate buffer of pH 12.5 as a catalyst. A stable fluorescent derivative of HFIP is formed within 5 min. The HFIP-FMOC derivative is separated by reversed-phase chromatography with isocratic elution on an octadecyl silyl column (33x4.6 mm, 3 microm) and guard column (20x4.0 mm, 40 microm), at 35 degrees C, and detected by fluorescence detection at an excitation wavelength of 265 nm and an emission wavelength of 311 nm. The method detection limit is 40 pg, per 10-microl injection volume, corresponding to 16 microg/l of HFIP in urine. The among-series relative standard deviation is <6% at 200 microg/l (n=6). As a preliminary application, the method was used to detect HFIP concentration in the urine of two volunteers exposed for 3 h to an airborne concentration of sevoflurane in the order of 2 ppm.

Biological and environmental monitoring of exposure to airborne benzene and other aromatic hydrocarbons in Milan traffic wardens.

Environmental and biological monitoring of airborne aromatic hydrocarbons has been performed in 20 policemen working as traffic wardens exposed to motor vehicle exhausts and in 19 peers employed as clerks. Airborne benzene, toluene, ethylbenzene and xylene concentrations, measured during the workshift, resulted in significantly higher outdoor than indoor concentrations (benzene and related aromatic hydrocarbons mean values, respectively of 53 and 350 micrograms/m3 vs. 29 and 180 micrograms/m3). Blood benzene, toluene, ethylbenzene and xylene concentrations did not differ significantly between indoor and outdoor workers; no differences were found between values obtained at the beginning (07:30 h) and the end of shift (00:30) in either group. Blood hydrocarbon concentrations seem to reflect airborne pollution, whilst the blood benzene concentration determined after the workshift poorly reflects airborne benzene morning peaks. Endshift blood benzene mean concentration in smokers (462 ng/l, n = 9) differs significantly from non-smokers (292 ng/l, n = 39).

Inaccuracy quality control in the monitoring of trace metal concentrations in biological fluids.

Quality assurance in trace element analysis requires continual surveillance of the accuracy and precision of results. A review of difficulties encountered in performing quality control programs of trace metal analysis in biological fluids is presented. Examples to clarify the inadequacy of available biological reference materials for quality control in biological monitoring of environmental and occupational low level exposure to metals are reported.

The speciation of the chemical forms of arsenic in the biological monitoring of exposure to inorganic arsenic.

Total As content may be determined in blood and urine by means of an AAS method that involves reduction of As to its volatile hydride and ashing at 600 degrees C with MgO and Mg (NO3)2. Separation of inorganic As (InAs), monomethylarsonic acid (MMA) and dimethylarsinic acid (DMAA) by ion-exchange chromatography, followed by direct AAS analysis, allows the determination of each As species in the urine. In a reference population of 148 subjects with only normal environmental exposure to As, total As concentration in the urine averages 17.2 +/- 11.1 micrograms/l. Urinary As consists of 10% each of InAs, MMAA and DMAA, the remaining 70% consisting of other forms of organic As. Blood As concentration averages 5.1 +/- 6.9 micrograms/l and correlates significantly with the urinary concentration of InAs and the sum of its metabolites (InAs + MMAA + DMAA). Inorganic arsenic undergoes methylation in the organism. After ingestion of high quantities of As2O3, the time course of excretion of its metabolites indicates that As methylation occurs by a saturable mechanism. In workers exposed to As2O3, InAs, MMAA and DMAA are the only chemical forms of As excreted in the urine that are relevant to a study of occupational exposure. Blood As concentration is proportional to exposure and correlates only with urinary DMAA excretion; DMAA seems to be the most appropriate single indicator of exposure. At high levels of exposure (total As excretion above 200 micrograms/l), As accumulates in the organism and DMAA excretion reflects its accumulation. At low levels of exposure (total As excretion below 50 micrograms/l) a short-term accumulation does not occur and the best biological indicator of exposure is InAs excretion. Seafood ingestion brings about a marked increase in urinary excretion of total As that lasts for 24-48 h and is not accompanied by any increase in InAs, MMAA or DMAA excretion. Organic As from seafood does not mix with the pool of inorganic As in the organism and may be separately detected in urine. In the biological monitoring of human exposure to As, particularly in the case of high urinary values, the speciation of the chemical forms of As in urine is necessary in order to establish with certainty the source, industrial or alimentary, of exposure.

Difficult hernia repair in the elderly. A particular case.

A particular clinical case personally observed is described. On the basis of this case it is evaluated if it can be correct to implant a mesh in potentially contaminated areas, if preperitoneal repair is the best approach in recurrent or difficult hernia repair and if there are specific contraindications in operating elderly patients.

[Assessment of exposure to polycyclic aromatic hydrocarbons during road paving]. / Valutazione dell'esposizione a idrocarburi policiclici aromatici nella stesura di asfalto.

Asphalt is a mixture of bitumen, (its fumes contain about 1% of polycyclic aromatic hydrocarbons, PAH), and mineral matter. 18 Workers were investigated during road paving to assess PAH exposure by environmental air-monitoring (the 16 most relevant, according to the American Environmental Protection Agency, EPA) and biological monitoring (urinary 1-hydroxypyrene excretion). Our results show that PAH exposure in these workers is not higher than that observed in traffic policemen working in urban areas.

[European multicenter cross-sectional study on exposure to low doses of benzene]. / Studio trasversale multicentrico europeo su esposizione a basse dosi di benzene.

A cross-sectional multicenter european study has been carried out to evacuate the relations between exposure to low level of benzene and biological markers of internal dose (t,t-MA, S-PMA) and early biological effect (DNA-SSB). The research has shown significantly increased levels (adjusted for smoking habits) of the urinary excretion of t,t-MA, S-PMA and DNA-SSB in petrochemical workers (mean benzene level = 5,694 micrograms/m3) but not in filling station attendants, traffic police officers, and bus drivers compared to referent workers. Dose-response relations were detected between benzene air levels, t,t-MA, S-PMA and DNA-SSB in petrochemical workers, with significantly increased levels of DNA-SSB detected for benzene exposure levels in the range 391-1,800 micrograms/m3 (0.12-0.58 ppm).

[New biomarkers of exposure]. / Nuovi indicatori di esposizione.

In this paper we have defined the new biomarkers of exposure (NBE) as those biomarkers discovered in the last five years and, among previously validated biomarkers, also those applied in different ranges of doses or those determined in biological matrices which differ from matrices originally considered. We examined the results from the surveys carried out by the main Italian research units involved in biological monitoring, i.e. those from the Universities of Brescia, Milan, Naples, Padua, Parma, Pavia, Turin and Verona. The data were collected using a standardized model and included the following: type of element or organic compound, type of biomarker, analytical technique and method, their relationship with environmental monitoring data, their relationship with effect indicators or effects in general, improvement with respect to old biomarkers, reference values. Twenty two NBEs were identified: 14 elements and chemical compounds as such or as metabolites, 4 examples of mixtures, 3 of new matrices, one of speciation. Among the others, aspects such as interest in requiring NBE, quality assurance, availability, cost-benefit ratio were discussed. We conclude that development of this specific field of research appears to be a crucial point for future improvement in risk assessment and health surveillance procedures.

[Biological monitoring of occupational exposure to airborne pollutants]. / Il monitoraggio biologico della esposizione professionale ad inquinanti aerodispersi.

Biological monitoring of inert substances requires knowledge of the mechanisms regulating respiratory absorption. The authors examine the influence of parameters such as work load, exposure duration and biotransformation on the respiratory absorption of inert airborne pollutants in the workplace. Attention is also given to the possibility of using biological thresholds or Biological Equivalent Limits (BELs).

[Acute exposure to vanadium-containing dusts: the health effects and biological monitoring in a group of workers employed in boiler maintenance]. / Esposizione acuta a polveri contenenti vanadio: effetti sulla salute e monitoraggio biologico in un gruppo di lavoratori addetti alla manutenzione delle caldaie.

The authors describe an episode of acute intoxication due to inhalation of vanadium-containing dusts in a group of 10 workers during maintenance work inside a boiler of an oil-fired electricity power station. Historical, clinical and biological monitoring data concerning the acute exposure phase and subsequent checks are presented. The appearance of irritative symptoms of the upper airways, green tongue (in 6 out of 10 subjects) and the values of urinary excretion of vanadium (means = 92, D.S. = 47 micrograms/l: limits 20-270 micrograms/l) indicated acute vanadium exposure. With the use of appropriate individual protection devices and shorter shifts, 2 weeks after the episode there was a complete remission of the symptoms and a return of urinary vanadium concentrations to 38, D.S. = 26 micrograms/l. Checks made 6 months, 1 and 2 years later did not reveal any alterations in the general blood chemistry parameters and the urinary vanadium concentrations were below 1 microgram/l (reference value). As already often reported in the literature, this episode confirms the danger involved in working in the presence of fuel oil residues or ashes and the need to adopt appropriate prevention measures.

[Determination of blood bile acids using high pressure liquid chromatography: comparison of chromatographic, enzymatic and immunoenzymatic methods]. / Determinazione degli acidi biliari serici mediante cromatografia liquida ad alta pressione: confronto tra metodi cromatografici, enzimatici e immunoenzimatici.

A method has been developed for measuring serum conjugated bile acids by HPLC. Serum samples, to which the internal standard is added, are purified by a solid phase procedure and injected on a reverse phase C18 column. Elution is accomplished by means of a flow gradient and peaks are detected at 198 nm. The detection limit ranges between 0.05 and 0.20 mumol/l for different analytes; between-day precision (CV 5.8%), working linear range (up to 50 mumol/l) and recovery (87%) were established. Comparison of the results obtained with HPLC, enzymatic and immuno-enzymatic methods gave high correlation coefficients. The method was applied for diagnostic purpose to a group of subjects suffering from various liver diseases. Also, 106 healthy workers, not occupationally exposed to known or potentially hepatotoxic agents, were studied in order to establish reference values for use in biological monitoring of chronic low level exposure to solvents. The method has the advantage of a more simple procedure compared to previously reported HPLC methods and appears to be well suited for routine use in toxicological and clinical test laboratories.

[The biological monitoring of occupational exposure to anesthetic gas and vapors: the determination of nitrogen protoxide, halothane and isoflurane in the urine]. / Monitoraggio biologico dell'esposizione professionale a gas e vapori anestetici: determinazione di protossido d'azoto, alotano e isofluorano nell'urina.

A gas-chromatographic method has been developed for measuring urinary nitrous oxide, halothane and isoflurane concentrations. A volume of head-space gases obtained from biological samples is analyzed by ECD-GC on a steel column (2 mm ID) serially packed with Porapak Q (1.2 m) and MS-5A (0.30 m), operated at 160 degrees C. The detection limit (ranging from 0.03 micrograms/l for halothane to 1 microgram/l for nitrous oxide), between-day precision (CV < 6%) and working linear range (up to 100 micrograms/l for halothane and 2000 micrograms/l for nitrous oxide) were determined. A two-year experience in biological monitoring of occupationally exposed surgical staff with the proposed method is reported and confounding factors are discussed. The method is easy to perform, free from interferences and suitable for use in routine analysis in toxicological laboratories.

[Biological limits of exposure: evolution of interpretative and methodologic criteria]. / Limiti biologici di esposizione: evoluzione dei criteri interpretativi e metodologici.

Biological monitoring is an extremely efficient investigation tool in evaluation of exposure to exogenous substances, in both occupational and environmental settings. However, although biological tests have been widely acclaimed as the ideal approach to or as a completion of environmental measurements, they have had difficulty in becoming firmly established due to a number of limitations of various nature. Besides the numerous uncertainties in the set-up phase, which depend on the choice of indicators or criteria for their use, difficulties are still incurred in making a univocal interpretation of the results. These difficulties are due to the limited pharmaco-kinetic information available on the various substances and to the wide variability in individual biological response. The possibility of extrapolating Biological Exposure Limits (BELs) from the corresponding TLV-TWA, by means of calculations based on the experimental regressions observed between internal and external dose indices, has up to now been considered a dubious operation from a formal point of view and merely indicative for practical purposes. This paper examines the possibility of establishing BELs that are fixed taking account of the influence of the various biological variables, thus permitting a more correct, objective and generalised use of biological indicators in current practice. From the regression function and relative tolerance limits, intended as a range of values within which regression values can be expected to be found with a probability that can be fixed a priori, it is possible to calculate 3 BEL values for each environmental TLV-TWA concentration. The question of which of these different values should be selected as a BEL for practical purposes must be solved on the basis of a series of observations related to the type of investigation being performed and the context in which the results are to be used. It should be emphasized that each BEL value has its own particular sensitivity and specificity, i.e., the possibility of correctly classifying the exposure conditions in relation to the environmental values. If sensitivity and specificity values are known, it is possible to calculate the predictive value of the biological measurements compared to the environmental measurements; if numerical data on these parameters are available, account can be taken of the variability of the results in a rigourously scientific manner.(ABSTRACT TRUNCATED AT 400 WORDS)

[Biological monitoring of environmental benzene exposure in traffic wardens]. / Monitoraggio biologico dell'esposizione ambientale a benzene in addetti alla vigilanza urbana.

Vehicle exhausts are a well known source of aromatic hydrocarbon pollution in urban environments. The paper reports the results of environmental and biological monitoring of benzene exposure in traffic wardens carried out over a 5-hour workshift. Subjects (n = 131) were grouped according to smoking habits and job task as follows: group (A) 52 nonsmoking office workers, (B) 43 nonsmoking outdoor workers, subdivided into (B1) 36 working on foot and (B2) 7 cyclists; (C) 20 smokers office workers, (D) 16 smokers outdoor workers, subdivided into (D1) 11 working on foot and (D1) 5 cyclists. The median indoor environmental benzene concentration (26 micrograms/m3, n = 50) was significantly lower than the outdoor concentration (45 micrograms/m3, n = 43) (p < 0.01); median exposure value of cyclists was 78 micrograms/m3 (n = 12). For biological monitoring, urinary excretion of trans,transmuconic acid was determined in spot samples collected at 7:30 h (MAit) and 12:30 h (MAft). The MAftA median value (63 micrograms/l, range 2-242 micrograms/l) was not statistically different from MAftB (74 micrograms/l, range 15-216 micrograms/l), while the MAftB2 value of 96 micrograms/l was higher than both MAftB1 (71 micrograms/l) and MAftA. In group (B) there was a relationship between airborne benzene levels and MAftB excretion (y = 17.2 + 1.1x, r = 0.62, n = 35, p < 0.01). The influence of smoking on urinary MA excretion was studied by comparing the results obtained in all nonsmokers (AB) with smokers (CD). MAftCD (192 micrograms/l) was significantly higher than MAftAB (69 micrograms/l) (p < 0.01). In smokers, statistically significant relationships were observed between urinary excretion of MAft (y, microgram/l) and cotinine (x, microgram/l) (y = 83 + 0.08x, r = 0.73, n = 23, p < 0.01), and smoking (x, number cigarettes/day) (y = 87.4 + 4.4x, r = 0.53, n = 29, p < 0.01). Comparison between MAft and MAit median excretion values, calculated for each of the 6 exposure groups, showed that MAft was always higher than the corresponding MAit value. A rough estimate of the total dose of benzene ("index of exposure", EI) inhaled by each subject during the 5-hour working shift as a consequence of air pollution and smoking was also made. Considering the entire group of subjects, a significant association was observed between EI and MAft values (y = 43.4 + 0.39x, r = 0.65, n = 104, p < 0.01). Individual values of MA it were correlated with MAft according to the equation y = 43.6 + 0.82x (r = 0.62, n = 105; p < 0.01) and were also positively associated with EI values (y = 42.3 + 0.20x; r = 0.55; n = 74; p < 0.01). In conclusion, the results suggest that the measurement of urinary MA excretion is a poor indicator for assessing environmental benzene exposure at levels below 100 micrograms/m3, such as those seen in this study; MA can however be reliably used as a biomarker for higher exposures such as those, for example, due to smoking.

[Biological monitoring of exposure to solvents: a method for the gas-chromatographic determination of aromatic hydrocarbons in the blood and urine]. / Monitoraggio biologico dell'esposizione a solventi: metodo per la determinazione gascromatografica degli idrocarburi aromatici nel sangue e nell'urina.

A gas chromatographic procedure with dynamic head-space purge and trap preconcentration (HSGC) and FID detection for blood and urinary benzene, toluene, ethylbenzene and xylenes (BTEX) determination at low level exposure is described. Critical steps (sample collection, calibration, HSGC conditions, contamination control) are discussed. The calibration curve is linear in the range 50 ng/l-500 micrograms/l; the calculated detection limit is 50 ng/l for all the considered aromatic hydrocarbons (AH) both in blood and urine; the within-day precision, calculated as variation coefficient (CV) at 400 ng/l and 40 micrograms/l (n = 6) was respectively CV = 13% and CV = 6% for all the studied analytes. The recovery rate was in the range 29-70%, depending on the hydrocarbon and matrix (blood or urine) considered. The procedure was applied to the biological monitoring of 151 workers occupationally or environmentally exposed to BTEX. Occupationally exposed subjects showed blood AH levels of 2-4 order of magnitude higher than environmentally exposed subjects. In white-collar workers exposed to BTEX urban pollution a significant difference in blood and urine levels of AH was observed between nonsmokers and smokers. Nonsmokers showed blood AH median values of respectively benzene = 241 ng/l, toluene = 759 ng/l, ethylbenzene = 140 ng/l, xylenes = 604 ng/l. Significatively higher BTEX blood values were observed in smokers after a median consumption of 5 cigarettes in 5 hours; observed median values were respectively: benzene = 365 ng/l toluene = 1327 ng/l, ethylbenzene = 233 ng/l, xylenes = 794 ng/l.