Budapesti Műszaki és Gazdaságtudományi Tanszék, Alkalmazott Biotechnológia és Élelmiszertudományi Tanszék, Környezeti Mikrobiológia és Biotechnológia Kutatócsoport
- Fémek, félfémek és vegyületeik
The advantage of the plant test with Sinapis alba is that it provides results on the bioavailable metal content of the soil in only one week instead of several weeks. The test allows also the study of organic metal uptake by plants. On the other hand the test is easy to be performed, does not need special qualifications, the sample amount and the lab equipment requirement is low, therefore the costs are low.
It is primarily used to measure the metal uptake of plants from the soil.
In case the soil is susceptible to mould forming the plants start to get rotten in the Petri dish after the third day. Plant growth is inhibited in case of very toxic soils. This can be avoided by running more parallel tests. The soil grains stuck on the plant roots are not easy to be washed. For this reason the test is mainly recommended for measurement of metal uptake by shoots. The soil can be removed from the roots by washing shortly with diluted hydrogen sulphate.
5-5 grams of soil from the air dried, chrushed and sieved (1-2 mm mesh), autoclave or dessicator sterilised soil samples are put and uniformly distributed in a 10 cm diameter Petri dish. It is uniformly wetted with 2.5-3.5 ml tap water and sterilised for half an hour in UV light. 40 white mustard (Sinapis alba) seeds are placed on the surface of the soil at equal distance from each other. The samples are kept in dark for 5 days in thermostate at 20°C. After the 3rd day they are additionally wetted with 0.25 ml of tapwater. After 5 days the shoots and roots of the grown plants are cut and separated by a non metallic piece such as plastic knife, are washed with tap water and are air dried at room temperature. Then the samples are sent to chemical analysis. Usually two parallel tests are run from one soil sample.
The plants are digested in the mixture of hydrogen peroxide and hydrogen nitrate and the extract is subjected to ICP-AES analysis.
The advantage of the method is that as opposed to the general bioaccumulation tests running for several weeks, this method gives the results in one week on the available metal content in the soil for plant uptake. The test is easy to be performed, does not need special qualifications, the sample amount and the lab equipment requirement is low, therefore the costs of the biological part are low.
In case the soil is capable of quick and intensive mould forming the plants start to get rotten in the Petri dish after the third day.
Plant growth is inhibited in case of very toxic soils thus there will be not enough biomass produced for accurate analysis. This can be avoided by running more parallel tests.
The soil grains stuck on the plant roots are not easy to be washed away so that the remaining grains may falsify the measurements. For this reason the test is mainly recommended for measurement of metal uptake by shoots. The soil grains can be removed from the roots by washing shortly with diluted hydrogen sulphate.
The chemical analysis of the plants metal content varies according to the analysed metal and applied analytical method. This cost component should be taken into account separately.
The test can be further developed to measure the likely to be accumulated organic substance uptake.
The test can be combined with biomass measurement, shoot and root elongation measurement ecotoxicological test.This way a single test provides information also on soil toxicity. This test can be used also in case of sediment or water.
No special hazards exhibited by this method.
There is no rapid bioaccumulation test described in the literature. This test is a combination of biotest and chemical analysis.
www.ecorisk.hu
Feigl Viktória: Rapid ioaccumulation test with Sinapis alba, Study, LOKKOCK projec, in Hungarian
Feigl, V.; Atkári, Á.; Uzinger, N, és Gruiz, K.: Fémmel szennyezett területek integrált kémiai és fitoremediácója – Siófoki Országos Környezetvédelmi Konferencia és Szakkiállítás kiadványa, 2006. szeptember 19–21, pp. 99–107
Feigl, V., Atkári, Á., Anton, A. and Gruiz, K.: Chemical stabilisation combined with phytostabilisation applied to mine waste contaminated soil in Hungary – Advanced Materials Research Vols. 20–21 (2007), pp. 315–318, Trans Tech Publications, Switzerland