In the context of solving pollution problems, what is/are the advantage/advantages of bioremediation technique?

1. It is a technique for cleaning up pollution by enhancing the same biodegradation process that occurs in nature.

2. Any contaminant with heavy metals such as cadmium and lead can be readily and completely treated by bioremediation using microorganisms.

3. Genetic engineering can be used to create microorganisms specifically designed for bioremediation.

Select the correct answer using the code given below:

The correct answer is 1 and 3 only.

Step-by-step Explanation:

Statement 1: Bioremediation is a biotechnical process that uses naturally occurring or introduced organisms (such as bacteria, fungi, and plants) to consume and break down environmental pollutants into less toxic or non-toxic substances. It effectively relies on enhancing naturally occurring biodegradation processes in nature. Therefore, Statement 1 is correct.

Statement 2: Heavy metals such as cadmium and lead are inorganic elements. Unlike organic contaminants, heavy metals cannot be biodegraded or destroyed by microorganisms. While microorganisms can alter their oxidation state or bioaccumulate them, heavy metals cannot be readily and completely treated or broken down by bioremediation. Therefore, Statement 2 is incorrect.

Statement 3: Genetic engineering is widely applied in bioremediation to create recombinant or genetically modified microorganisms (GEMs). For instance, organisms like Pseudomonas putida (known as the "superbug") have been engineered to degrade specific complex pollutants, such as crude oil components. Therefore, Statement 3 is correct.

Hence, statements 1 and 3 are correct, making the correct option 1 and 3 only.