Eco Toxicological Survey Of Sediments Of Navotas River Via Allium Cepa

Navotas City is known as the "Fishing Capital of the Philippines" and it is located north of Manila. As the "Fishing Capital of the Philippines" Navotas is considered as a network which is exceptionally dependent in fishing as 70% of its populace determining their work specifically or in a roundabout way through fishing. In this case the city do not just settle for small scale fishing, In fact they have developed into a Marine Industrial State. In this city many Shipyard companies have been built. According to Shipbuilding and Ship Repair Entity with Facilities Manpower and Capitalization Office in 2017 there, are about 47 enlisted and registered shipyard companies in Metro Manila and 30 of them were located in Navotas. Near or alongside the Navotas River there are a lot of shipyard companies were addressed. This river is a stream located nearby Tangos, Daanghari, Gasak In Navotas and the said river is also part some areas in Malabon specifically Hulo and Flores in Malabon, It is also close at Tanza Boundary Bridge. It is a stream with a coordinates of 14°40’35’’N 120° 55’48’’E. This serves as one of the main sources of water in the locality of Navotas. Having about 30 shipyards alongside this river can cause a lot of river pollution not only because of those waste of workers but also the scrap metals and other metallic substances that may contain in those ships that were parked alongside the watercourse. Metals scraps and other metallic substances can be a threat in the purity of the watercourse that similarly include heavy metals. Heavy metals are elements that has a high atomic weight.

Heavy metals and natural radionuclides are often allocated unusually within ecosystem sections. Being the main river in Navotas it must be a clean one, because inhabitant here uses the water in almost everything. Scrap, metals and other metallic substances can contaminate and mix with the sediments below the river. In nature, the sediments were carried and deposited over time and this is connected to the river history. Sediments are solid material that are moved and deposited in a new location. Sediment can consist of rocks and minerals, as well as the remains of plants and animals. It can be as small as a grain of sand or as large as a boulder. The distribution, enrichment, and accumulation of heavy metals in the sediments, especially those at the vicinity of tributary estuaries of Kaohsiung Harbor, Taiwan were investigated. Sediment samples from six locations in the Kaohsiung Harbor were collected quarterly in the period from 2002 to 2005 and characterized for metal content (e. g. , Hg, Pb, Cd, Cr, Cu, Zn and Al). Extensive sample material from river sediments of Carinthia (Austria) was investigated with regard to the contents of heavy metals that are relevant to the environment, Zn, Cd, Pb, Cu, Cr and Ni.

The common onion, Allium cepa, has been used in plant bioassays since the 1930s in what is known as Allium test. The Allium test is a simple and reliable method used in toxicity monitoring and has been proposed as a standard in environmental monitoring and as one of the tests routinely used for assessing chromosomal damage induced by chemicals. As a short-term test, the Allium test offers many advantages such as ease of handling, low cost, and good chromosome conditions, which allow visualization of chromosome damage or disturbance of cell division including the examination of risks of aneuploidy.

The Allium test also combines two test targets, namely, cytotoxicity and mutagenicity. Cytotoxicity is measured by growth inhibition, while mutagenicity is correlated to the rate of chromosome breaks. In addition, the Allium test is a sensitive assay that gives comparable results to other test systems. Hence, positive results in the Allium test may be taken as a warning and also an indication that the chemical being tested may pose a risk to humans and other organisms and to the environment.

The Allium cepa assay will determine the components and heavy metal content of the sediments from Navotas River through the effects of sediments from the river in Navotas to the chromosomes of Allium cepa. Through this research, the content of heavy metal in Navotas river sediments will provide a basis on the toxicity and water pollution of the river. The presence of heavy metal on the sediments will administer ground on its effects to aquatic organisms. Through Allium cepa assay, does the sediments from Navotas River exhibit heavy metal content. The mitotic index and some nuclear abnormalities are used to evaluate cytotoxicity and analyze micronucleus to verify mutagenicity of different chemicals. Moreover, the A. cepa test system provides important information to evaluate action mechanisms of an agent about its effects on the genetic material (clast genic and/or a eugenic effects). In the face of all the advantages that the A. cepa test system offers, it has been widely used to assess the impacts caused by xenobiotics, characterizing an important tool for environmental monitoring studies, where satisfactory results have been reported.