Scientific Validators
Our published research papers and articles about air quality are inspired by nature and our commitment to innovating for the future. Stay informed and up-to-date with our informative content.
Foliage plants for removing formaldehyde from contaminated air inside energy-efficient homes and Future Space Stations (NASA)
Abstract:
A sealed, plexiglas chamber with temperature and humidity control and illuminated externally with wide spectrum grow lights was used to evaluate the ability of golden pothos (Soindapaua aureus), nephthytis (Syngoniun podophyllum), and sweet potato (Ipomoea batatas) to remove formaldehyde from contaminated air at initial concentrations of 16-19 ppm. Under the conditions of this study, the two low light- requiring plants, golden pothos and nephthytis, proved more efficient by removing 3874 and 3849 ug formaldehyde in the first 7h of exposure, respectively. The sweet potato removed approximately 50% less. The immediate application of this new technology should be in energy-efficient homes which have a high risk of this organic concentrating in the air due to outgassing of urea-formaldehyde foam insulation, particleboard, fabrics and various other synthetic materials. In addition, this technology is applicable to air purification and revitalization in future space stations which use biological means for developing a closed ecological life support system.
Fungal Phytoremediation of Heavy Metal-Contaminated Resources: Current Scenario and Future Prospects
Abstract:
Heavy metal (Pb, Cd, Cr, Ni, As, Se, etc.) contaminations in fertile soils and fresh water are one of the worldwide growing issues along with the modernization of the life style. Contamination in natural resources due to heavy metals is a serious threat to sustainability of ecosystems and human life. A special urge is needed to restore the natural resources in its natural state. Based on the contamination type, various site-specific physical, chemical, and biological bioremediation strategies could be applied. However, the major limitation of physicochemical approaches is its higher cost and relatively low competence. Conversely, the biotic action of contaminated environment is slightly economical and ecologically attractive alternative to the present physicochemical methods of treatment. Among different bioremediation techniques, phytoremediation and mycoremediation are having its merit of eco-friendliness. Microorganisms play an important role in heavy metal bioremediation from contaminated resources attributed to its easy operation, without any secondary pollution and showing higher efficiency at low metal concentrations. Mycoremediation is the utilization of fungi for remediation of the contaminated natural resources. Unlike bacteria, the fungal phytoremediation does not require absolute water phase as fungus can grow of air-water interface. The pH, moisture, substrate, and species specificity are the important factors which highly influence the fungal phytoremediation. This chapter mainly emphasizes the detailed mechanism of fungal phytoremediation. Some potential species are provided for abatement of heavy metals from contaminated water and soil. The heavy metals toxicity, stress response and their impact on humans as well as on plants are described in brief. Further, it also highlights the utilization efficiency of fungal phytoremediation for sustainable removal of toxic heavy metals from contaminated natural soil and water resources.
Evaluation of air flow through an active green wall biofilter
Abstract:
Green walls show promise as active bio-filters to improve indoor air quality by removing both gaseous and
particulate air pollutants. The current work represents a detailed assessment of airflow through an active green
wall module. Airflow distribution through the module, the effect of wetting the substrate, and the effect of
introducing a cover to the module’s open top face were investigated, with the aim to improve the module’s
design and achieve more appropriate and effective airflow. Four cases of both planted and unplanted modules under both dry and wet conditions are considered. This work’s primary observation is that more air will pass through a typical green wall substrate, and hence become cleansed, when the substrate is saturated wet more than when it is dry.
The increase was substantial at approximately 50% more with 14.9 ± 0.2 L/s total air flow rate passing through the wet planted module versus 10 ± 0.2 L/s when dry. Reducing the 15.5 ± 0.75% of airflow passing through the module’s open top face was found to be essential to maximize the bio-filtration capacity. Adding a top cover to the module having six 10 mm holes for irrigation decreased the airflow through the top by 6 ± 0.75%, and directed it through the filter increasing the percentage of air flow passing through the front openings from 79 ± 4% to 85 ± 4%.
A review of green systems within the indoor environment
Abstract:
This paper reviews the state of art of vegetation systems and their effect on the indoor environmental
quality (IEQ), based on scientific studies from the past 30 years. Some studies have shown that biophilic
workspaces and interaction with plants may change human attitudes, behaviours, improve productivity
and the overall well-being. Evapotranspiration from plants helps lowering the temperature around the
planting environment and this can be utilised for air cooling and humidity control. Also, indoor greenery
can be used to reduce sound levels as a passive acoustic insulation system. Living wall systems in
combination with biofiltration are emerging technologies to provide beneficial effects on improvement
of indoor comfort. Several studies have indicated that green systems may improve indoor air quality
and that they have different pathways for pollutant removal of volatile organic compounds. The plant
root zone in potted plants may be an effective area for removing volatile organic compounds under
controlled conditions.
In conclusion, the full capacity of plants in real-life settings will need to be clarified
to establish the true pollutant-removal mechanisms and the general effect on IEQ. The effects of green
systems in combination with mechanical elements such as conventional heating, ventilation and air
conditioning would need to be studied.
Lead tolerance in plants: strategies for phytoremediation
Abstract:
Lead (Pb) is naturally occurring element whose
distribution in the environment occurs because of its exten-
sive use in paints, petrol, explosives, sludge, and industrial
wastes. In plants, Pb uptake and translocation occurs, caus-
ing toxic effects resulting in decrease of biomass produc-
tion. Commonly plants may prevent the toxic effect of
heavy metals by induction of various celular mechanisms
such as adsorption to the cell wall, compartmentation in
vacuoles, enhancement of the active efflux, or induction of
higher levels of metal chelates like a protein complex (met-
allothioneins and phytochelatins), organic (citrates), and
inorganic (sulphides) complexes. Phyotochelains (PC) are
synthesized from glutathione (GSH) and such synthesis is
due to transpeptidation of γ-glutamyl cysteinyl dipeptides
from GSH by the action of a constitutively present enzyme,
PC synthase. Phytochelatin binds to Pb ions leading to
sequestration of Pb ions in plants and thus serves as an
important component of the detoxification mechanism in
plants. At cellular level, Pb induces accumulation of reactive
oxygen species (ROS), as a result of imbalanced ROS
production and ROS scavenging processes by imposing
oxidative stress. ROS include superoxide radical (O2),
hydrogen peroxide (H2O2) and hydroxyl radical (OH), which are necessary for the correct functioning of plants;
however, in excess they caused damage to biomolecules,
such as membrane lipids, proteins, and nucleic acids among
others. To limit the detrimental impact of Pb, efficient strat-
egies like phytoremediation are required. In this review, it
will discuss recent advancement and potential application of
plants for lead removal from the environment.
Phytoremediation of particulate matter from indoor air by Chlorophytum comosum L. plants
Abstract:
Higher plants, including spider plants, are able to
take up and degrade/detoxify various pollutants in the air.
Although nearly 120 plant species have been tested for indoor
air phytoremediation, to the best of the authors’ knowledge,
data on particulate matter (PM) phytoremediation from indoor
air are not yet available in literature. This work determined the
ability of spider plants to take up PM, one of the most harmful
pollutants to man, in the indoor air of five rooms housing
different activities (a dental clinic, a perfume-bottling room, a
suburban house, an apartment and an office). It was found that
spider plants accumulate PM of both categories (water wash-
able and trapped in waxes) and in all three size fractions
determined and that the amount differed depending on the
type of activity taking place in the particular rooms ranging
from 13.62 to 19.79 μg/cm2
. The amount of wax deposited on
the leaves of plants grown in these rooms also differed (34.46–
72.97 μg/cm2
). The results of this study also demonstrated
that the amount of PM accumulated on aluminium plates was
always significantly lower than that accumulated on the
plants’ leaves, showing that more than simply gravity forces
are involved in PM accumulation on leaf blades.
Phytoremediation of Air Pollutants: Prospects and Challenges
Abstract:
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Literature review: Science behind nature-based air pollutant mitigation (Phytoremediation)
Abstract:
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Potted-plant/growth media interactions and capacities for removal of volatiles from indoor air:
The Journal of Horticultural Science and Biotechnology,
Summary:
Results are presented of an investigation into the capacity of the indoor potted-plant/growth medium microcosm to remove air-borne volatile organic compounds (VOCs) which contaminate the indoor environment, using three plant species, Howea forsteriana (Becc. (Kentia palm), Spathiphyllum wallisii Schott. ‘Petite’ (Peace Lily) and Dracaena deremensis Engl. ‘Janet Craig’. The selected VOCs were benzene and n-hexane, both common contaminants of indoor air. The findings provide the first comprehensive demonstration of the ability of the potted-plant system to act as an integrated biofilter in removing these contaminants. Under the test conditions used, it was found that the microorganisms of the growth medium were the “rapid-response” agents of VOC removal, the role of the plants apparently being mainly in sustaining the root microorganisms. The use of potted-plants as a sustainable biofiltration system to help improve indoor air quality can now be confidently promoted. The results are a first step towards developing varieties of plants and associated microflora with enhanced air-cleaning capacities, while continuing to make an important contribution to the aesthetics and psychological comfort of the indoor environment.
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Efficiency of volatile formaldehyde removal by indoor plants: contribution of aerial plant parts versus the root zone:
The Journal of the American Society for Horticultural Science
Abstract:
The contribution of aerial plant parts versus the root zone to the removal of volatile formaldehyde by potted Fatsia japonica Decne. & Planch. and Ficus benjamina L. plants was assessed during the day and night. The removal capacity of the entire plant, aerial plant parts, and root zone was determined by exposing the relevant parts to gaseous formaldehyde (2 μL·L−1) in airtight chambers (1.0 m3) constructed of inert materials. The rate of formaldehyde removal was initially rapid but decreased as the internal concentration diminished in the chamber. To compare the removal efficiency between species and plant parts, the time interval required to reach 50% of the initial concentration was determined (96 and 123 min for entire plants of F. japonica and F. benjamina, respectively). In both species, the aerial plant parts reduced the formaldehyde concentration during the day but removed little during the night. However, the root zone eliminated a substantial amount of formaldehyde during the day and night. The ratio of formaldehyde removal by aerial plant parts versus the root zone was similar for both species, at ≈1:1 during the day and 1:11 at night. The effectiveness of the root zone in formaldehyde removal was due primarily to microorganisms and roots (≈90%); only about 10% was due to adsorption by the growing medium. The results indicate that the root zone is a major contributor to the removal of formaldehyde. A better understanding of formaldehyde metabolism by root zone microflora should facilitate maximizing the phytoremediation efficiency of indoor plants.
UBreathe Rain: ‘A nature-inspired and HEPA-free , wall mounted, modular air purification system for a large semi-open region having heavy population influx.
Abstract:
Urban Air Labs have developed a self-sustaining air
purification system in the form of modules which can be stacked together and mounted on the wall to cater to the large air-volume.
The air-purification method backing this system is an innovative sustainable development over our patent filed ‘Breathing Roots Technology’ also hereby called as bio-filtration. The bio-filtration i.e. plant's phytoremediation capabilities coupled with our novel and patent filed ‘Rain Shower Technology’. The rain shower
technology mimics the wet deposition phenomenon that happens during rainfall which has been proven to reducing
suspended pollutants in the air.[11] This is further supported by a novel self-regenerating filter made of sodium alginate, this filter needs not to be replaced and is also sustainable in development and usage.