Chemistry homework help. Hello, I am looking for someone to write an article on Bacteria cross contaminants. It needs to be at least 7000 words. After 24 hours of growth on both MacConkey and r2a plate, small growth was observed in all the samples. Similarly after 48 hours, large colonies were observed on both media for samples ec1 and ec2 but this was relatively higher on ec5 and ec 6.After undertaking Gram staining, it was observed that all the samples on both media had Gram positive bacteria. Catalase test indicated positive results on all the samples. According to the result findings, the most probable bacteria identified were all cocci, bacilli, and spirilla. Besides, sample ec5 and ec 6 seems to have high levels of cross contamination. These tests have been explored in the next section. Chapter 1: Introduction 1.1 Background By definition, Cross contamination is the transfer or physical movement of bacteria that are harmful from one place, person or object to another. It is a major factor which contributes to food poisoning, and it consists of 4 common sources that include people, work surfaces, food and equipment. Harmful bacteria live in or can be on our bodies, particularly around or on hands and faces as well as on clothing (McKillip, 2011). Due to the fact that they exist in small numbers they never cause a disease. If it happens that, there is a transfer of these bacteria from the clothes or bodies to food, and then given a chance to multiply, it can lead to food becoming unsafe to be eaten. Bacteria have the ability to multiply and live in any crevices and cracks in equipment including the chopping boards surface cuts. After using the equipment, food bits with bacteria can remain. If there is no proper cleaning of the equipment, there will be transfer of bacteria to another food when it is used next. Surfaces including bench tops might have bacteria on them as a result of contact with people, also dirty equipment, raw foods or other things like cartons stored on the floor can contribute. If there is no proper cleaning of bench tops, there might be bacterial contamination of any food that is placed on them. The main objective of the study was to ascertain the level of cross-contamination during cleaning in an office environment 1.2 Main Concepts and Theory Cross contamination is a major factor which contributes to food poisoning. The contaminants (Bacteria) can be transferred from the clothes or bodies to food, and then when given a chance to multiply, it can lead to food becoming unsafe to be eaten. Bacteria have the ability to multiply and live in any crevices and cracks in equipment including the chopping boards surface cuts. Most of these contaminants are harmful to humans and can cause diseases when they enter the body. 1.3 Objective of Research To determine the level of cross-contamination during cleaning in the office environment 1.4 Structure of dissertation. The dissertation is divided into 6 sections. first section covers the background of the main concept explored in the study, second section explores literature review on methods and type of bacteria found in the study, this enabled the understanding of the available methods that have been ever done successfully then borrowed the idea to the current study.