Environmental Impact and Health Effects of Hydrogen

Hydrogen, the first element in the periodic table, is aaggravated by overexposure to hydrogen. When
colorless, odorless and insipid gas, formed by itsinhaled a harmful concentration of this gas in the air
diatomic molecules, in normal conditions. Thewill be reached very quickly.
hydrogen atom is formed by a nucleus with one unitHeating may cause violent combustion or explosion
of positive charge and one electron. It’s one ofas the gas reacts violently with air, oxygen, halogens
the main compounds of water and of all organicand strong oxidants causing fire and explosion hazard.
matter, and it’s widely spread not only in theMetal catalysts greatly enhance these reactions. High
Earth but also in the entire Universe. There are threeconcentrations in the air cause a deficiency of
hydrogen isotopes: protium, mass 1, found in moreoxygen with the risk of unconsciousness or death.
than 99,985% of the natural element; deuterium,We must check oxygen content before entering a
mass 2, found in nature in 0.015% approximately, andsuspected area as there is no odor warning if toxic
tritium, mass 3, which appears in small quantities inconcentrations are present. We may measure
nature, but can be artificially produced by varioushydrogen concentrations with suitable gas detector
nuclear reactions.  (a normal flammable gas detector is not suited for
 the purpose). In case of inhalation problem we should
Hydrogen forms 0.15 % of the earth's crust and it isshut off its supply. In case it not possible and there
the major constituent of water. 0.5 ppm of hydrogenseems no risk to surroundings, let the fire burn itself
H2 and variable proportions as water vapor areout; in other cases extinguish with water spray,
present in the atmosphere. Hydrogen is also a majorpowder, carbon dioxide. In case of fire we should
component of biomass, constituting the 14% bykeep its cylinder cool by spraying with water. One
weight. Hydrogen occurs naturally in the atmosphere.must combat fire from a sheltered position and rush
The gas will be dissipated rapidly in well-ventilatedfor medical aid and advice in case of all inhalation and
areas. Any Effect of hydrogen on plants or animalscontact cases.
would be related to oxygen deficient environments.Deuterium
No adverse effect is anticipated to occur to plant life,Deuterium is the stable, nonradioactive isotope of
except for frost produced in the presence of rapidlyhydrogen, commonly called heavy hydrogen because
expanding gases. No evidence is currently available onits atomic weight is approximately doubles that of
the effect of hydrogen on aquatic life.ordinary hydrogen, but it has identical chemical
 properties. Deuterium has about twice the atomic
Hydrogen is the most flammable of all the knownweight of normal hydrogen because its nucleus
substances. It is slightly more soluble in organiccontains a proton and a neutron, instead of just a
solvents than in water. Many metals absorb hydrogen.proton. Hydrogen as it occurs in nature contains
Hydrogen absorption by steel can result in brittleapproximately 0.02 percent of deuterium that was
steel, which leads to faults in the chemical processthe first isotope to be separated in a pure form from
equipments. At normal temperature hydrogen is a notan element. Several methods have been used to
very reactive substance, unless it has been activatedseparate the isotope from natural hydrogen. The two
somehow; for instance, by an appropriate catalyser.processes that have been most successful have
At high temperatures it’s highly reactive.been fractional distillation of water and a catalytic
Although in general it’s diatomic, molecularexchange process between hydrogen and water. In
hydrogen dissociates into free atoms at highthe latter system, when water and hydrogen are
temperatures. Atomic hydrogen is a powerfulbrought together in the presence of a suitable
reductive agent, even at ambient temperature. Itcatalyst, about three times as much deuterium
reacts with the oxides and chlorides of many metalsappears in the water as in hydrogen. Deuterium has
to produce free metals. It reduces some salts toalso been concentrated by electrolysis, centrifuging,
their metallic state and reacts with a number ofand fractional distillation of liquid hydrogen. The nuclei
elements, both metals and non-metals to produceof deuterium atoms, called deuterons, are much used
their hydrides. Atomic hydrogen  reacts with organicin research in physics because they can be readily
compounds to form a complex mixture of products.accelerated by cyclotrons and similar machines and
The heat released when the hydrogen atomsused as “atomic bullets” to transform an
recombine to form the hydrogen molecules is usedatom of one element into another element.
to obtain high temperatures in atomic hydrogenDeuterium also has important uses in biological
welding.  research as a tracer element for studying problems
 of metabolism.
The most important use of hydrogen is the synthesisRegular hydrogen and deuterium are not normally
of ammonia. The use of hydrogen is extendingmetallic, meaning they are not shiny or malleable.
quickly in fuel refinement, like the breaking down byScientists have used pressure and heat, however, to
hydrogen (hydrocracking), and in sulphur elimination.force deuterium to act like a metal, making it shinier
Huge quantities of hydrogen are consumed in theand easier to compress. Studying deuterium in
catalytic hydrogenation of unsaturated vegetable oilscompressed and highly hot conditions can help
to obtain solid fat. Hydrogenation is used in thescientists understand how hydrogen behaves in the
manufacture of organic chemical products. Hugehot, heavily pressurized interiors of planets and in the
quantities of hydrogen are used as rocket fuels, ininteriors of stars. The use of heavy water as a
combination with oxygen or flour, and as a rocketmoderator in atomic piles has been suggested and
propellant propelled by nuclear energy. Hydrogen canDeuterium, either in deuterium oxide or in lithium
be burned in internal combustion engines. Hydrogendeuteride, and tritium are essential components of
fuel cells are being looked into as a way to providenuclear fusion weapons, or hydrogen bombs.
power and research is being conducted on hydrogen 
as a possible major future fuel. For instance it can beTritium
converted to and from electricity from bio-fuels,Tritium is the radioactive hydrogen isotope of atomic
from and into natural gas and diesel fuel, theoreticallymass 3 and symbol 1H3 or T. The nucleus of a tritium
with no emissions of either CO2 or toxic chemicals.atom consists of a proton and two neutrons. It
 undergoes decay by beta emission to give a helium
As hydrogen is extremely flammable, its manynucleus of mass 3; it has a half-life of 12.26 years.
reactions may cause fire or explosion. As the gasTritium is produced in a number of ways, including the
mixes well with air, explosive mixtures are easilybombardment of deuterium compounds with
formed. Moreover the gas is lighter than air. The gashigh-energy deuterons and by the absorption of
can be absorbed into the body by inhalation and highneutrons by the lithium isotope of mass 6. Some
concentrations can cause an oxygen-deficienttritium is produced in the upper levels of the
environment. Individuals breathing such anatmosphere by the bombardment of nitrogen with
atmosphere may experience symptoms which includeenergetic neutrons produced by cosmic rays;
headaches, ringing in ears, dizziness, drowsiness,rainwater is usually found to contain minute amounts
unconsciousness, nausea, vomiting and depression ofof tritium. The enormous amount of energy released
all the senses. The skin of a victim may have a bluewhen tritons react with deuterons in the so-called
color. Under some circumstances, death may occur.nuclear-fusion process makes tritium an important
Hydrogen is not expected to cause mutagenicity,constituent of hydrogen bombs. Tritium is also used
embryotoxicity, teratogenicity or reproductiveas a tracer in chemical and biochemical research.
toxicity. Pre-existing respiratory conditions may be