Aims of the investigation were to evaluate toxicity of monoethanolamine waste to various microorganisms and plants; and to search for means accelerating waste biodegradation. The results of the investigation show toxic effects of MEA waste on bacteria, fungi and plant seeds at rather low concentrations. Some microorganisms are able to adapt to the pollutant in the mixed substrates of the MEA and peat. During the experiment, density of the bacterial and fungal populations in the MEA and peat mixed substrates increased, followed by the intensive acidifying process of the substrates and by the degradation of pollutant. Strong negative effect of MEA waste on peat microbial communities was determined during the first day of the experiment; respiration rate significantly decreased as compared with peat control. Inhibition rate depended on the MEA waste content in the mixture, peat pH and incubation time. After 3–4 days of the incubation, respiration rate of the MEA mixture with acid peat at lower MEA concentration exceeded that of the control by almost five times. Respiration rate of the MEA mixture with neutral peat gradually increased after 4 days of incubation, and was stimulated by the addition of NPK fertilizers. Introduction of yeasts complex and the fungus Trichoderma harzianum accelerated the process of degradation, moreover, the phytotoxicity of the mixed substrate decreased significantly. Santrauka Darbo tikslas – įvertinti monoetilamino (MEA) atliekų toksiškumą įvairių grupių mikroorganizmams ir augalams bei parinkti būdus atliekų biodegradacijai pagreitinti laboratorinėmis sąlygomis. Nustatytas gana mažų koncentracijų MEA dervinių atliekų toksinis poveikis bakterijoms, mielėms, grybams ir augalams. Dalis mikroorganizmų durpių ir MEA mišinyje prisitaiko prie teršalų, didėja jų populiacijos tankis, mažėja substrato pH, o tai rodo MEA atliekų degradaciją, vykstančią dėl mikroorganizmų veiklos. Stiprus mikroorganizmų bendrijos aktyvumą slopinantis MEA poveikis pastebėtas pirmąją eksperimento parą; mikroorganizmų kvėpavimo intensyvumas, palyginti su kontrole, žymiai sumažėjo. Poveikio kvėpavimo intensyvumui mastas priklausė nuo MEA atliekų kiekio mišinyje, durpių pH ir ekspozicijos trukmės. Po trijų parų mikroorganizmų kvėpavimo intensyvumas nedidelės koncentracijos MEA ir rūgščių durpių mišinyje beveik penkis kartus buvo didesnis nei kontrolės. MEA dervos mišiniuose su neutraliomis durpėmis nustatyta palaipsnis kvėpavimo intensyvumo didėjimas substratą papildžius (NPK) trąšomis. Nustatyta, kad introdukavus mielių kompleksą ir mikromicetą Trichoderma harzianum į MEA ir durpių mišinio substratą, mikroorganizmų pradai išlieka gyvybingi ir vystosi, skatindami MEA biodegradaciją. Tai rodo žymiai sumažėjęs su durpėmis sumaišytų MEA atliekų toksiškumas augalams. Резюме Целью работы было оценить токсичность моноэтиленаминных (МЭА) смолистых отходов для разных групп микроорганизмов и растений, а также найти способы ускорения биодеградации этих отходов в лабораторных условиях. Установлено токсичное воздействие сравнительно небольших концентраций МЭА на бактерии, дрожжи,грибы и растения. Часть микроорганизмов в смеси МЭА и торфа приспосабливается к загрязнителям, увеличивается плотность их популяции, рН субстрата меняется в кислотную сторону, что указывает на деградацию МЭА отходов, происходящую благодаря деятельности микроорганизмов. Сильное воздействие МЭА, угнетающее активность сообщества микроорганизмов, наблюдалось в первые сутки эксперимента: интенсивность дыхания посравнению с контрольными данными значительно уменьшилась. Степень воздействия на итенсивность дыханиязависела от количества МЭА отходов в смеси, кислотности торфа и времени экспозиции. Спустя трое суток интенсивность дыхания в смеси МЭА отходов небольшой концентрации и торфа с кислой реакцией была почти впять раз больше, чем в контроле. В смеси МЭА и торфа нейтральной реакции установлено постепенное увеличение интенсивности дыхания при обогащении субстрата удобрениями NPK. Установлено, что при интродукциикомплекса дрожжей и микромицета Trichoderma harzianum в субстрат смеси МЭА и торфа их пропагулы остаютсяжизнеспособными и размножаются, способствуя биодеградации МЭА отходов. Данный вывод подтверждает значимое уменьшение токсичности смеси МЭА отходов и торфа по отношению к растениям.

The majority of the plants secrete their enzymes in the soil, where they can decompose various organic compounds. Extra cellular plant enzymes can be effective against a number of contaminants. To estimate the plants, their enzymes and micro-organism effect on hexadecane content in the soil, the sterile soil samples was amended with 0.5 % hexadecane and sowed with accordingly prepared rye seeds. Till increasing the quantity of micro-organisms and the formation of rye seedlings, hexadecane content remained practically unchanging in all samples. After 21 days hexadecane content in the soil with rye seedlings was about 5 % of the contributed content. The intrinsic soil processes through 21 days to shrank the hexadecane content in the soil without rye seedlings up to 17 %. Oxidases, catalases and peroxidases were detected in rye biomass during all test period. As shown by the results, polyphenoloxydases were detected only in root biomass, the early germs of germination and roots formation stages.

The vegetation cover of two sites contaminated with heavy fractions oil products:Klaipeda State Oil Terminal (KSOT) of 130,000 sq. m area, and Pauoscio RailwayStation (PRS) of 60,000 sq. m area-has been investigated.It has been established, that phytotoxical effect begins with heavy oil concentrationsreaching I 000 g/m2 or 5 000 mg per l kg of dry soil. Such heavy oil containsp-edominantly tar (by 55 percent) and light hydrocarbons (below C28) composed of thefollowing factions (in percentage): paraffin-naphtene hydrocarbons - 15, olefins andcyclodiolefines -5, alkilaromatic - l, alkidiaromatic -4, polyaromatic -20.Also, plant species and communities have been identified. The KSOT site has been foundto nurture 271 species of vascular plants. The most part of this flora consists of referralplants aD'.I those specific for littoral sands. The most polluted area has been found tonurture 38 plant species.The most resistant to the fuel oil pollution are plants having long rootstocks and longtaproots: Calamagrostis epigejos, Carex hirta, Elytrigia repens, Leymus arenarius, Poacompressa, Artemisia campestris, Cirsium arvense, Convolvulus arvensis, Tanacetumvalgare, Tussilago farfara. Some of them can be used in ex-situ remediation of the oilpolluted soil at biodegradation ranges. They can also be used as model plants inexperimental selection of cultivated plants for bioremediation purposes.

The present study was undertaken to evaluate the efficacy of introduced indigenousbacterial isolates for ex situ bioremediation of fuel oil contaminated soil. For this purposethree hydrocarbon-degrading indigenous bacterial isolates were screened from petroleumoil contaminated soil and repeatedly used for inoculation of fuel oil contaminated soil.The total petroleum hydrocarbons (TPH) content was determined by gravimetric method,Hydrocarbon fractions (alkanes, aromatics, asphaltenes and resins) present in TPH wereobtained by silica gel column chromatography. The study showed that some introducedbacterial isolates effectively adapted to the contaminated soil. The bioaugmentation effectwas calculated to raise the numbers of bacteria by approximately one order of magnitudefrom the indigenous population at the site. Ex situ study showed that the introducedbacterial consortium effectively adapted to the local environment of the soil at thebioremediation site.Our results indicated that disappearance of TPH from inoculated soil samples dependedon the general soil impurity, term of bacterial treatment, level of TPH contamination andindividual microorganism efficacy. With application of bacterial consortium andfertilizers, the TPH level was reduced to 60 - 66% after three months.

Monoethanolamine (MEA) solutions are widely used in for gas cleaning from carbon dioxidefor many industrial purposes. Spent MEA solutions should be properly decontaminated andsafely disposed. As these processes proceed at high temperature, the MEA solutions produceand accumulate tars and other degradation products as well as heavy metals from thecorroding equipment.This report presents a biological method for the detoxification of spent MEA solutions. Asolution is mixed with soil in order to inoculate aerobic microorganisms decomposing organicsubstances; and the obtained substrate is spread on a flat and properly hydro-isolated ground.To strengthen the vitality and increase activity of the microorganisms, the substrate is aerated,humidified, fertilized and its pH is monitored and controlled. When the MEA concentration isreduced, vascular plants (Calamagrostis epigejos, Secale cereale, Salix viminalis) areimplanted in the substrate, and their growth concludes the detoxification.