An environmental risk assessment for a DDX-contaminated agricultural area in Turkey: soil vs. plant or human vs. animal.

This study is the first research attempt to assess the environmental risks of an agricultural area contaminated with the p,p'-DDT and its metabolites (DDX) on human and terrestrial species through exposure to soil and agricultural products, simultaneously. The study was carried out for a DDX-contaminated agricultural area in Turkey. Soil samples obtained in two different harvest applications were analyzed in terms of DDX levels.

Effects of the lichen Peltigera canina on Cucurbita pepo spp. pepo grown in soil contaminated by DDTs.

Lichens consisting of a symbiotic association of green algae or cyanobacteria and fungi are found in a variety of environmental conditions worldwide. Terricolous lichens, located in soils, affect the living and lifeless environment of the soil due to their effective secondary metabolite and enzymatic content. Terricolous lichens can increase the biological, chemical, and physical usefulness of soil.

Inheritance profile of weathered chlordane and p,p'-DDTs accumulation by Cucurbita pepo hybrids.

Cucurbita pepo ssp pepo (zucchini) accumulates significant levels of persistent organic pollutants in its roots, followed by unexpectedly high contaminant translocation to the stems. Most other plant species, including the closely related C. pepo ssp ovifera (squash), do not have this ability.

Accumulation of weathered p,p'-DDTs in hybridized Cucurbita pepo cultivars.

Cucurbita pepo spp pepo (zucchini) is known as an exceptional weathered dichlorodiphenyldichloroethylene (DDE) accumulator, whereas Cucurbita pepo ssp ovifera (squash) is termed a nonaccumulator. Experiments were conducted with hybridized zucchini and squash to assess the inheritance pattern of DDX (the sum of p,p'-dichlorodiphenyltrichloroethane [p,p'-DDT], p,p'-dichlorodiphenyldichloroethane [p,p'-DDD], and p,p'-dichlorodiphenyldichloroethylene [p,p'-DDE]) accumulation potential in xylem sap and tissues of parental, F1 hybrids, and F1 backcross (BC) generations of plants. Plants were grown in pots containing soil with weathered DDX at 732 to 1,130 ng/g soil or under field conditions in soil with 322 to 2,700 ng/g.

Accumulation of weathered pp'-DDE in xylem sap of grafted watermelon.

Movement of weathered p,p'-dichlorodiphenyldichloroethane (p,p'-DDE) from contaminated soil to the rhizosphere pore water to the xylem sap of grafted watermelon was studied under green house conditions. p,p'-DDE concentrations in pore water and xylem sap was compared in intact plants, homografted, and compatible heterografts of Cucurbita pepo spp. pepo and Citrullus lanatus plants.

Accumulation of weathered p,p'-DDTs in grafted watermelon.

The grafting of melon plants onto cucurbit rootstocks is a common commercial practice in many parts of the world. However, certain cucurbits have been shown to accumulate large quantities of weathered persistent organic pollutants from the soil, and the potential contamination of grafted produce has not been thoroughly evaluated. Large pot and field experiments were conducted to assess the effect of grafting on accumulation of weathered DDX (the sum of p,p'-DDT, p,p'-DDD, and p,p'-DDE) from soils.

Uptake and translocation of p,p'-dichlorodiphenyldichloroethylene supplied in hydroponics solution to Cucurbita.

Field studies show shoots of zucchini (Cucurbita pepo L.) accumulate various hydrophobic contaminants from soil, although many other plants do not, including cucumber (Cucumis sativus L.).

Soil amendments, plant age, and intercropping impact p,p'-DDE bioavailability to Cucurbita pepo.

Field experiments were conducted to optimize the phytoextraction of weathered p,p'-DDE (p,p'-dichlorodiphenyldichloroethylene) by Cucurbita subspecies. The effects of two soil amendments, mycorrhizae or a biosurfactant, on p,p'-DDE accumulation was determined. Also, p,p'-DDE uptake was assessed during plant growth (12, 26, 38, and 62 d), and cultivars that accumulate weathered p,p'-DDE were intercropped with cultivars known not to have that ability.

Influence of citric acid amendments on the availability of weathered PCBs to plant and earthworm species.

A series of small and large pot trials were conducted to assess the phytoextraction potential of several plant species for weathered polychlorinated biphenyls (PCBs) in soil (105 microg/g Arochlor 1268). In addition, the effect of citric acid on PCB bioavailability to both plants and earthworms was assessed. Under small pot conditions (one plant, 400 g soil), three cucurbits (Cucurbita pepo ssp pepo [zucchini] and ssp ovifera [nonzucchini summer squash], Cucumis sativus, cucumber) accumulated up to 270 microg PCB/g in the roots and 14 microg/g in the stems, resulting in 0.

Uptake by cucurbitaceae of soil-Bome contaminants depends upon plant genotype and pollutant properties.

Three Cucurbitaceae, Cucurbita pepo L. subsp. pepo (cv.

Accumulation of weathered polycyclic aromatic hydrocarbons (PAHs) by plant and earthworm species.

Experiments were conducted to assess the bioavailability of polyclycic aromatic hydrocarbons (PAHs) in soil from a Manufactured Gas Plant site. Three plant species were cultivated for four consecutive growing cycles (28 days each) in soil contaminated with 36.3 microg/g total PAH.

Influence of nutrient amendments on the phytoextraction of weathered 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene by cucurbits.

Field experiments were conducted to determine the impact of nutrient amendments on the phytoextraction of weathered 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (p,p '-DDE) by eight cultivars of cucurbits over a single growing season. Four cultivars of Cucurbita pepo ssp pepo are accumulators and extract percent level quantities of persistent organic pollutants (POPs), whereas C. pepo ssp ovifera and Cucumis sativus are nonaccumulators.