Assessment of intraocular pressure (IOP) in subjects exposed to ultrafine particles atmospheric pollution (overall evaluation).
G. Oliva1, D. Di Clemente 2, , F. Perri4, M. Manigrasso 5,, C. Vernale 5, F. Bailardi1,, P. Avino 5, C. Giannico 4, EM Vingolo 3 ASL TA 1/1, Taranto 2 ..................................................................... 3 University “Sapienza� of Rome Polo Pontino 4 NAIL - Sector Research, Certification and Verification - Territorial Department of Taranto 5 Chemical Laboratory, DIPIA, THE NAIL, Rome
Corresponding Author: Daniele Di Clemente M.D.,
Abstract - In this research the authors intend to verify possible alterations of the intraocular pressure (IOP) in subjects long term exposed to atmospheric ultrafine particles pollution. purpose of the research is to identify if the ultrafine particles air pollution, in addition to the already known airway disease, is able to impact on the mechanisms of IOP regulation of IOP, altering the delicate balance of the functions and structures nutritive, refractive and circulatory human eye.
Key words:
intraocular pressure, tonometry, ultrafine particles, urban air pollution
Introduction: effects of air pollution on
groups and d work, expanding the sample
human health are well known and for long
previously
time discussed in literature, particularly
residents for a total of 312 patients in the city
regarding the effects on morbidity and
of Taranto. For each of them has been
mortality.
examined clinically, eye and a general
Epidemiological
studies
have
investigated,
measurement
to ultrafine particles and effects involving
applanation tonometry. Statistical analysis of
human health.
data was performed using chi- framework
acquisitions
also
indicate
that
IOP
with
examining
shown a linear relationship between exposure
Recent
of
and
Goldmann
completed with Yates correction.
exposure to particles in suspension containing metals (such as particles from fossil fuels
Results - In this phase of the research was no
used for cars), may cause a wide spectrum of
statistically significant in differences of
inflammatory responses in the respiratory
intraocular pressure values in the two groups
tract and in the cardiovascular system
(Taranto Tamburi and City).
(cellular
cell
Were no statistically significant differences
permeability), possibly in relation to their
particularly in males, in women of post-
metal components and carbon dioxide high
menopausal osteoporosis, as well as in
concentrations.
workers in heavy industry.
Objectives - In this study, the Authors check
Conclusions - It can be said to have found in
and evaluate deeply potential impact of
this investigation significant variations de
pollution agents derived from the ultrasmall
alteration of IOP in the exposed and control
particles in relationship to possible variations
groups (Tamburi Taranto and Taranto City),
of the intraocular tension in particularly
in relation to a greater or lesser density of air
exposed subjects.
pollutants, in particular ultrafine particles
The analysis was conducte in the city of
present in the atmosphere. It would be
Taranto on residents in the neighborhood
appropriate to continue the investigation and
Taranto Tamburi (area closely near the steel
examinate, in addition to the modifications
factory industrial zone), compared with those
hydrodynamic of intraocular fluids, the
residents in the remaining areas of the city.
possible alterations in the posterior segment
damage
and
increased
of the eye, due to pollution damage and Materials and methods - In the period
insults, by blood, could endanger the retinal
January '11 December '12 has focused
structures and vitreous body.
attention on groups most at risk by sex, age
Another
aspect
not
to
be
overlooked,
Introduction
connected to the physical characteristics of
The current experimental and epidemiological
ultrafine powders, is related to the fact that
evidence locates in airborne finer particles the
while the powders of larger settle to the
responsibility of a variety of diseases, not
ground, the effect of gravity, in the immediate
only in respect of the respiratory trait, but also
vicinity and within short times, compared to
of other organs, which would be affected in
the point and at the moment issue, the finer
particular by the particles belonging to the
ones can travel long distances and remain
ultrafine size class, as already shown in
suspended in the air for hours or days after
previously made investigations [1, 2].
issuance, however, difficult to maintain the
The particulate matter in urban environments
original size, because of the high tendency to
is commonly divided into two main groups:
coagulate / accumulate.
coarse
border
Low and ultrafine particles (PUF) penetrate
"dimensional" between these two groups
through the nasal mucosa and conjunctiva,
generally ranges between 1 and 2.5 microns.
which explains why it was investigated
In fact, the boundary between the coarse and
whether this insult can somehow determine
the fine is usually conventionally established
significant changes in intraocular pressure
in aerodynamic diameter of 2.5 microns. The
regulation.
term ultrafine (PUF), recently introduced,
The IOP is that delicate mechanism that keeps
refers to particles with an aerodynamic
in balance the structures nutrients, refractive
diameter less than 0.1 microns (100 nm)
and circulation of the eyeball.
(Figure 1) [3,4].
The production of the circulating fluid inside
Focusing on the component relative to the
the eye (aqueous humor), on which the IOP,
PUF, becomes relevant to observe different
is driven by the ciliary body. We can
parameters from the aerodynamic diameter,
distinguish a intraocular phase for production
such as the numerical concentration of the
and a phase of resorption.
particles and the surface area. Indeed, ultra-
Reabsorption occurs through the complex
fine contribute only minimally to determine
structure
the mass of PM 10 or PM 2.5, quantified by the
meshwork). [5]
gravimetric method, but constitute the most
The IOP is considered normal Between 14
important component in terms of the number
and 18 mmHg. Circadian variations are
of mini particles and, albeit to a lesser degree,
present
of the total surface area.
modifications of Âą 2 mmHg. For example, the
and
fine
dust.
The
of
in
the
all
chamber
subjects
with
(trabecular
possible
IOP is higher than it fits the early morning
hours and then stabilized in the course of the
−
urea
day. [6,7,8]
−
amino acids
The compensatory mechanisms triggered by
−
Na (greater than in the serum), K,
these physiological changes prevent the
Ca, bicarbonates, chlorides, ascorbic
occurrence of any damage to the structures of
acid, CO
the anterior segment and posterior segment of
blood)
the eye (optic nerve) (fig ure. 2).
−
2
(values greater than in the
pH (7.1 to 7.3)
The aqueous humor, liquid stream undergoes
The IOP is determined by the balance
continual renewal, plays a key role in
between production and outflow of aqueous
ensuring a certain consistency to the eyeball
humor.
(intraocular pressure), which is higher than
Increases in IOP may be related to:
atmospheric pressure.
−
It is essential to maintain the proper
from
arrangement of the structures necessary for refractive vision. E 'linked to the activity of
blockage,
block
intrascleral,
increased
episcleral venous pressure [9].
−
fluid and amniotic fluid) tensional
(Production
canalicular structures; −
increases episcleral venous pressure (obstruction of the veins or ciliary mediastinal
syndrome,
The glaucoma, disease characters by an increase in IOP (even if there are so-called low-pressure glaucoma), determines where
and
resorption) −
inflammation
pericarditis, pulmonary emphysema).
nutrients (poverty of protein, rich in salts, values similar to cerebrospinal
−
ciliary
mechanical lock of trabecolo-
swirling,
The aqueous humor has features: −
the
(thickening of acqueous humor);
secretory ciliary processes and can be changed where overproduction, or trabecular
increase to the volume of secretion
compensatory mechanisms are not sufficient, a progressive degeneration of the fibers of the
dioptric (refractive index of 1.33 similar to that of the crystalline lens)
optical ner vo, with consequent damage of the vision periferic to initially (detected by visual
Constituent elements of the aqueous humor
field examination), and severe deficit of
are:
central vision in the final stages [10]. − −
protein enzymes
(5.16 mg/100cc) (Hyaluronidase,
carbonic anhydrase, proteases) −
glucose
−
lactic acid
Etiopathogenesis of chronic glaucoma, there would be a progressive obliteration of the arterio-capillary networks in uveal tissuetyping load of sheets and nervous.
The
most
widespread
and
precise
Survey results for these subgroups are shown
methodology for the determination of the IOP
in Tables III รท IV.
is tonometr ia applanation that exploits the
Each sub-group was divided further by
law of Imbert - Fick for which the pressure of
considering two age groups: 23 รท 46 years
a sphere can be derived by evaluating the
and> 46 years getting res ultati presented in
force necessary to flatten a small portion of its
tables V to VI II.
surface. In clinical use the Goldmann
A
tonometer,
of
extrapolating from the two groups starting
applanation has a diameter of 3.5 mm, for
only individuals (male) employees in large
which the theoretical volume of liquid
industrial towns. The last indagin and
displaced to obtain the flattening of this
conclusive data are shown in Table IX.
segment is 0,004 mmc, quantity irrelevant in
Of each patient was performed a clinical
the context of bulbar content.
examination and a general ophthalmological
You run instilling an anesthetic eye drops,
measurement of IOP, repeated for three times
and is colored with sodium fluorescein
a distance za of twenty days, with the
corneal surface, and finally shall be measured
Goldmann
with
anesthesia surface with benoxinato chloride
in
Goldmann
which
the
applanation
surface
tonometer
(Figure 3) [11].
final
comparison
was
applanation
made
tonometer
by
after
and staining of the corneal surface with sodium fluorescein. We excluded all those who had previous illnesses borne by the
Materials and methods
anterior segment of the eye, or already
Were investigated in the period from January
suffering from glaucoma, or contact lens
2011 to December 2012, 312 patients resident
wearers, or individuals who were subjected to
in the city of Taranto (Figure 4), 148 male
surgery or excimer laser.
and 164 female, between the ages of 23 and
Statistical analysis - The experimental results
71 years (Table I), which have undergone
were subjected to a test of statistical
specialist ophthalmology.
significance. How statistical test was used to
As regards their origin, 166 individuals are
test the significance of the ฯ 2.
residents of the district of Taranto Tamburi,
The niz ialmente assumed l 'the hypothesis
while the remaining 146 workers are coming
zero (or null hypothesis), according to which
from other areas of the city. (Table II).
there should be no difference between the
Were selected, then four distinct subgroups by
groups
sex, by division of the two original groups.
considered. According to the null hypothesis,
with
regard
to
the
parameter
the groups were equal between the gold and
the observed differences were attributable to chance. Obviously, the null hypothesis can be true or false. To check the veracity of zero it was necessary to analyze the data with an appropriate statistical test. If the test should accept the hypothesis zero, then the difference is not statistically significant. If the test instead recommended to reject the hypothesis zero, then the observed difference is declared statistically significant. The chi-square test is a non-parametric statistical test aimed at verifying whether the frequency values obtained by detection, are significantly different from the frequencies obtained with the theoretical distribution. The statistical analysis was completed by applying Yates correction that is used for a number of observations of less than 500 and RECITAL statistically significant P values <0.05 [1 2].
Results
It would be appropriate to continue the
The statistical analysis of experimental data
investigation and found, in addition to
obtained from observation, having compared
changes in hydrodynamic buoyancy eyepiece
the two areas under investigation, leads,
end, the possible alterations in the posterior
respectively, for the male patients, for women
segment of the eye, due to insults, even by
aged> 46 years (menopausal age) and for
blood, could endanger the fund vitreous-
workers male, to reject the null hypothesis
retinal and uveal .
with the consequent result that the differences are statistically significant and therefore can not be attributed to chance (Tables III, VIII and IX).
Conclusions Enquiries were made, there was a possible effect of air pollutants, specifically particulate air pollution ultrafine on the values of IOP. This effect is pronounced in male adults (especially in large-scale industry workers) and in women of menopausal age.
Bibliography
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10. G. Cristini , RA Meduri . Pathophysiological basis of clinical ophthalmology 1983 11. DJ Spalton , R. Hitchings , P. Hunter . Atlas of clinical ophthalmology 2006 2nd edition 12. T. Colton. Medical Statistics 1979
Demographic characteristics of the patients analyzed.
Table I
Males
Age ± SD
Female
Age ± SD
Total
148
42.2 ± 10.7
164
43.7 ± 12.8
Taranto Drums
81
39.5 ± 9.5
85
46.1 ± 13.9
Taranto City
67
46.2 ± 13.4
79
41.1 ± 13.7
Table II
Overview on the statistical analysis of data related to individuals total Pathological values
Normal values
Total
Taranto Drums
17
1 49
1.66
Taranto City
6
140
146
Total
23
290
312
χ = 4.28 2
P = 0.0 386
χ = 3.43 2
P = 0.0 642
Table I II
Statistically s ignificativa (P <0.05) Correction according to Yates Statistically not significant
Overview on the statistical analysis of data related to male individuals Pathological values
Normal values
Total
Taranto Drums
11
70
81
Taranto City
2
65
67
Total
13
135
148
χ = 5.14 2
Difference statistically significant (p <0.05) P = 0.023
χ = 3.90 2
P = 0.0483
Table IV
Correction according to Yates Difference statistically significant (P <0.05)
Overview on the statistical analysis of data related to female individuals Pathological
Normal values
Total
values Taranto Drums
6
79
85
Taranto City
4
75
79
Total
10
1 54
164
χ = 0, 28 2
Statistically not significant
P = 0.5936
χ = 0.0 4 2
P = 0, 8359
Table V
Correction according to Yates Statistically not significant
Overview on the statistical analysis of data related to male individuals (Age range 23 ÷ 46 years old) Pathological values
Normal values
Total
Taranto Drums
5
35
40
Taranto City
1
45
46
Total
6
80
86
χ = 3.52 2
Statistically not significant
P = 0, 0608
χ = 2.10 2
P = 0, 1469
Table VI
Overview on the statistical analysis of data related to male individuals (Age> 46 years old) Pathological values
Normal values
Total
Taranto Drums
6
35
41
Taranto City
1
20
21
Total
7
55
62
χ = 1.35 2
P = 0, 2450
χ = 0, 55 2
P = 0, 4602
Table VII
Correction according to Yates Statistically not significant
Statistically not significant Correction according to Yates Statistically not significant
Overview on the statistical analysis of data related to female individuals (Age range 23 ÷ 46 years old) Pathological
Normal values
Total
values Taranto Drums
1
47
48
Taranto City
1
52
53
Total
2
99
101
χ = 0.01 2
Statistically not significant
P = 0, 9436
χ = 0.42 2
P = 0, 5194
Correction according to Yates Statistically not significant
Overview on the statistical analysis of data related to female individuals (Age> 46 years
Table VIII old)
Pathological values
Normal values
Total
Taranto Drums
7
23
30
Taranto City
1
32
33
Total
8
55
63
χ = 5.84 2
Difference statistically significant (P <0.05) P = 0, 0156
χ = 4.16 2
P = 0, 0415
Table IX
Correction according to Yates Difference statistically significant (P <0.05)
Overview on the statistical analysis of data related to individuals male workers Pathological values
Normal values
Total
Taranto Drums
9
33
24
Taranto City
2
41
43
11
74
85
Total
χ = 5, 31 2
Difference statistically significant (p <0.05) P = 0, 0 212
χ = 3.92 2
P = 0, 0476
Correction according to Yates Difference statistically significant (p <0.05)
1