NANOPOLLUTIO

N

K.SAILAJA

TAM/2014/21

Nanotechnology is the manipulation of self-assembly of individual atoms, molecules, or molecular clusters into structures to create materials and devices with new or vastly different properties.

Nanotechnology has amazing applications

Nanoparticles have unique thermal, mechanical, magnetic and optical properties that allow for their widespread application in biomedicine and many industrial sectors .

More than 1310 marketed consumer products are based on nanomaterials .

Carbon nanotubes can be used for H fuel storage

The amazing applications of nanoparticles. Gold nanorods fight cancer, carbon fiber-polymer composites for lightweight (yet super-strong) materials, solar cells etc

Thin layers of gold are used in tiny medical devices

Early tumor detection, studied in mice

WHY TO STUDY ?

WHAT IS NANOPOLLUTION ? Nanopollution is the introduction of

nanosized contaminants in to the natural environment.

 Nanoscopic device or material manufacturing processes leave behind nanoparticles (smaller than a billionth of a meter) which can infiltrate the cells of humans, animals and all living organisms that may be unprepared for the influx of artificial particles.

FROM WHERE NANOPOLLUTANTS COMING ?

Nanopollutants are the components of nanopollution.

Nanopollutants may be coming from either:

Naturally occurring nano sized substances;

Nano sized substances that are strange to the environment (nanocontaminants).

There are two types of NPs

causing nanopollution:

Naturally occurring nanoparticles:some examples are ; Nanoparticles expelled by volcanoes

along with ash and other natural materials;

Nanoparticles naturally occurring on the ocean spray; formed by the violent burst of waves;

Nanoparticles naturally occurring in mineral composites.

Nanoengineered nanoparticles

(NENPs) or, in other words engineered nanoparticles.

NENPs recently came into existence through the processes of nanofabrication.

NENPs are nanoparticles produced by Humans that have been specifically designed for a specific function (e.g. packaging, coating, protection of radiation in sunscreens).

NENPs

What happens when nanoparticles present in the air ?

Mix with humidity also present in the air. Consequently, precipitation is

contaminated Precipitation reaches the soils and the open water (oceans, seas, rivers, lakes); 

Are incorporated in plants Are incorporated in animals through

respiration;  Contaminate food exposed to air;  Contaminate drinking water exposed to air;  Are mixed with open water (e.g. oceans,

rivers, streams, creeks, lakes);  Are infiltrated in soils

When nanoparticles present in the water:

Pass into the atmosphere accompanying the water vapour during the evaporation of water;

Contaminate soils (trough groundwater);

Are absorbed by roots of aquatic plants;

Are absorbed by aquatic animals;Contaminate food during the process

of washing with water and when water is used to cook.

When Nanoparticles present in soils:

Pass into the atmosphere accompanying the water vapour during the evaporation of water; 

Are absorbed by underground roots of terrestrial plants; 

Are absorbed by underground and terrestrial animals; 

Contaminate groundwater. 

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Why worry?

Inhaled nanomaterials have the potential to pass directly to the brain, and from the lungs into the blood stream.Ingested nanomaterialspass from the gut into the blood stream.

Nemmar et al, 2001, 2002. (Reviewed in Borm PJ, Kreyling W: J Nanosci Nanotechnol 2004, 4:521-531)

Nanoparticles cause pulmonary injury, hepatotoxicity, immunotoxicity , neurotoxicity , renal toxicity . Recently, severe pulmonary fibrosis also noticed.

What happens when infiltrate in to the human body ?

The female population is particularly vulnerable and deserves special attention because toxicity in this group may impact both female and fetal development

Silver nanoparticles (though they are not toxic to humans), dissolve in water and release silver ions (which are antibacterial).

If silver nanoparticles are released into the environment, these types of concentrated silver ion releases could devastate local bacterial populations, with drastic consequences for the affected ecosystems.

some man-made nanoparticles may be directly toxic to microbes, plants, and animals

Exposure of pregnant mice to Nanoparticles -Normal fetus and Malformed fetuses

There are also several types of nanomaterials that may be detrimental to the environment because they facilitate chemical reactions that can harm plankton, bacteria, and small animals.

Many metal and metal oxide nanomaterials are excellent catalysts (materials that speed up the rate of different chemical reactions).

If these catalytic nanomaterials are released into the environment, they can enable chemical reactions that generate toxic chemicals, such as free radicals or reactive oxygen species ( ROSs).

One of these nanomaterials is titanium dioxide (TiO2), which is an excellent photocatalst.

These reactive oxygen species are known to be harmful to many aquatic organisms, including plankton and small fish.

Single Ag nanoparticles causing deformation and death of zebra fish

Nanoparticle Pollution Affects Crop Growth

Nano-cerium accumulated around the soybeans roots and stunted plant growth and the nodules aren’t functional because of the cerium oxide.

Nano-zinc allowed crops to absorb much more zinc than plants grown in regular soil.

They are taken by bacteria .

For any disaster

Basic elements of a precautionary policy for nanomaterials:

Choosing the right nanoscale materials is one of the key parameters for the future direction of nanotechnology

Prohibit the untested or unsafe use of nanomaterials

Conduct full life-cycle impact assessments as a prerequisite to commercialization; assess nanomaterials as new substances, since unique physical properties impart unique hazard profiles

Facilitate full and meaningful participation by public and workers in nanotechnologies development and control; assess the social and ethical impacts of nanotechnologies

Engineering ethics need to be defined before the commercial use of nanotechnology.

Risk assessment on new nanomaterial based application is important to evaluate potential risk to our environment when the products are in use