Dechlorination of polychlorinated biphenyls, dibenzo-p-dioxins and dibenzofurans on fly ash.

Dechlorination of commercial mixtures of polychlorinated biphenyls (PCB) as well as polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) on extracted and non-extracted fly ash obtained from municipal waste incinerator (MWI) was studied in closed systems under nitrogen atmosphere at temperatures of 260 degrees C and 340 degrees C. Decomposition results (given as the difference between PCB or PCDD/F molar amounts before and after the experiment (in %) due predominantly to dechlorination reactions) and detoxification data (expressed similarly but related to toxic PCB and PCDD/F congeners only and given in I-TEQ units) are reported. Detoxification of Delor 105/80T at 260 degrees C and 340 degrees C at a loading of 0.65 wt%, was 99.48% and 100%, respectively. The decomposition of Delor 103 at 340 degrees C and for the loading of 0.75 wt%, corresponded to 99.99%. The detoxification capability of PCDD/Fs on extracted and non-extracted fly ash for loading of 130 and 264 ng/0.4 g of fly ash at 340 degrees C made 96 and 98%, respectively.

The effect of oils on PAH, PCDD, PCDF, and PCB emissions from a spark engine fueled with leaded gasoline.

The effect of synthetic and mineral oils on the formation of polyaromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) in emissions from a spark ignition engine was studied on a Skoda Favorit engine fueled with leaded gasoline. The test cycle simulated urban traffic conditions on a chassis dynamometer, in accordance with the ECC 83.00 test. The data for selected PAHs as well as PCDDs, PCDFs, and PCBs congener profiles are presented. PCDD/Fs emissions for an unused oil and the oil after 10000-km operation varied from 300 to 2000 fmol/m3, PCBs emissions from 75 to 178 pmol/m3, and PAHs emissions from 150 to 420 microg/m3. The content of PCBs in oils varied from 2 to 920 mg/kg.

Continuities and discontinuities in the development of 64 very small premature infants to 4 years of age.

The psychiatric, psychological, school and overall family functioning of 64 very small premature infants was assessed from birth up to 48 mnths of age. Results indicated that 43% of infants scored in the abnormal range on a behaviour rating scale filled in by the mothers and 24% on a teacher rating scale at age 4. However, only 11% of the children received a psychiatric diagnosis. Traditional attachment ratings at 1 yr were not related to psychiatric status at age 4, but family functioning was. Disturbed children had also suffered more perinatal difficulties.

Patterns of temperament variation in three groups of developmentally delayed preschool children: mother and father ratings.

Patterns of temperament variation in the developmentally delayed preschool population have not been adequately studied. The present paper reports temperament data for children 2 to 4 1/2 years old: 32 with Down's syndrome, 29 with neurological problems, and 35 with delays of unknown etiologies, as reported by their mothers and fathers. Results indicate that children in the total delayed sample are more approaching, less intense, less persistent, and have higher thresholds for stimulation than those in the normative sample. There were differences among the three groups in activity level, approach/withdrawal, and distractibility. Furthermore, on these three dimensions, mothers scored their children as more difficult than did fathers. These data highlight the need for adequate norms for subgroups of delayed children, and suggest that inclusion of temperament assessment can be a useful part of the clinical care of delayed children and their parents.

Family responses to developmentally delayed preschoolers: etiology and the father's role.

Parents of 59 developmentally delayed preschoolers (18 with Down syndrome, 19 with neurological problems, and with 22 unknown etiologies) responded to questionnaires and structured interviews to assess parental stress and support, locus of control, and self-esteem. There were group differences in maternal reports of positive experience with the child, self-esteem, reported support, and relations with grandparents. With the exception of self-esteem, all comparisons favored the Down syndrome group. Fathers reported fewer distress symptoms, higher self-esteem, more internal locus of control, and less support than did mothers. These findings indicate a need to understand individual differences among families of delayed children and illustrate that the effects of a child's handicap on fathers differ from those upon mothers.