Water contamination Flashcards
what do we need water for?
- food production
- industry (energy)
- domestic
- recreation
- habitat
contamination
presence of any substance other than water
might include naturally occurring salts
pollution
unwanted, dangerous material that’s introduced into earths environment due to human activity. threatens human health and harms ecosystems
types of contamination
biological, organic, inorganic, physical
how does pollution enter water bodies
point source e.g. sewage pipe
non point source e.g. land run off
sources of pollution
pharmaceuticals, heavy metals, petrol, microorganisms, fertilisers, thermal from industry, radioactive waste and from human activity
impacts of pollution
on health, environment and economy.
so many ways its hard to study and quantify
how many people died due to water pollution in 2014
1.8million
about heavy metals
naturally fond in crust and soils.
natural sources - weathering of soils, rocks and volcanic eruptions
anthropogenic sources - industrial waste, mining, corrosion of water pipes
trace amounts can be good for us
high levels lead to illness
arsenic
heavy metal
occurs naturally
known carcinogen for humans
can affect biodiversity
nitrates and phosphates
important for healthy growth of plants
in fertilisers
can be bad for humans - blue baby syndrome
environmental impacts of nitrates and phosphates in water
eutrophication
algal bloom
harmful to humans and animals if drink or swim in it
impacts can move up food chain
how many die worldwide due to water Bourne diseases each year ?
2.2 million
effects of sewage pollution
- recreational exposure to antibiotic resistant bacteria in sea=higher risk of gut colonisation by antibiotic resistant bacteria
- ruin aesthetics of envt and lead to beach closure
- eutrophication
- algal blooms
- illness outbreaks
how to measure water quality
standardised and validated methods are needed to compare across sites and time
how often? do they correlate?
threats to water quality
- population is growing
- demand for freshwater will be /3 greater
- increased demand for food
- changed in land use
- changing climate and hydrology
- plastics
- antibiotic resistance
- new chemicals
how to manage water bodies and protect water quality
- monitor
- reduce/prevent pollution
- improve treatment
- improve policies to protect water
whats an antimicrobial?
chemical that kills or prevents the growth of microorganism. can be natural, semisynthetic or synthetic.
they disrupt cell activities involved in survival and reproduction
antimicrobial resistance
bacteria can make cell walls more impermeable
how do microbes gain drug resistance
- genetically encoded
- vertical(parent to offspring) and horizontal gene transfer
co selection
plasmids can carry multiple resistance genes.
e.g. presence of heavy metals will select for bacteria with resistance genes for heavy metals, but also for any other genes on this plasma including antibiotic resistance genes
why is antibiotic resistance and increasing threat?
we keep developing new antibiotics and then have to develop a new one
what year was the first report where a woman was resistant to all antibiotics
2016 - she died
effects of antibiotic resistance
routine procedures now much more risky.
death
how many deaths are predicted due to antibiotic resistance by 2050
10million
antimicrobial resistance in aquatic environments
sewage contains antimicrobials and those resistant.
plastics have been shown to increase frequency of horizontal gene transfer events in water.
heavy metals can be co selecting agents for antibiotic resistance genes
