Laser printer emissions worse than smoking

[Michael Hopper]

See the attached for the news that a number of laser printers emit as
many particles into the air as does a smoker.

http://tinyurl.com/3x8btj

What is not expalined is whether these laser printers used OEM or
aftermarket cartridges. The latter would be more suspect.

Mike

 

[Barry Watzman]

Even if I accept this (I don't), the number of particles isn't the only
criteria. Toner is basically ground up plastic. It's pretty inert.
Not a carcinogen like cigarette smoke.

 

[Arthur Entlich]

This study is disconcerting, and important, since many of us work in
places with laser printers and photocopiers and some of us work on them
and their cartridges.

They studied 62 models of which 17 were considered high emitters.

They mention that 12 HP models and one Toshiba were in that high emitter
class. That's 13 of them, so there were 4 more, as well. I assume they
were probably newer models, but I don't know. I have not been able to
find the original article which lists all of the printers and their
emission levels.

I'm not sure one can assume remanufacturered or third party cartridges
are worse than OEM. The problem is the smaller the size of the toner
particles, the greater the risk of the particles entering the blood
stream, and also the greater risk of them being breathed in, and since
typically smaller particles provide higher print quality, it may be that
the higher quality may be from OEM products. Many laser printer
companies are quite proud to advertise that they have very small toner
particle sizes.

I would say that those of us who work with toner cartridges and laser
printers mechanically or with refilling are at greatest risk, however.

I think I best start wearing a face mask more regularly based upon this.

If anyone comes across the actual article, please post the link.

Art

 

[Arthur Entlich]

Depending upon the formulation, laser toner can include:

carbon black - a known carcinogen which has had some changes made in its
manufacturing, which has reduced the risks to an "acceptable" level

resins - (variable) they can include polystyrene, polyethylene and
others, they are not necessarily inert, however.

waxes - also not inert, in fact, many are organic in nature and
reactive, some may support growth of organic life such as molds and bacteria

dyes - vast range, some organic, some not, potentially carcinogenic

metal oxides and pigments depending upon the color of toner involved.

I would say the risks are possible, maybe even likely, if these
particles are reaching into deep lung tissue and entering the blood
stream, as they appear to be capable of doing. Upon heating and in use,
these components may have synergistic relationships and produce other
byproducts. Some laser printers also produce ground level ozone.

BTW, although the article still has not been released on the internet,
in doing some further digging, it appears the largest component of laser
printers tested were HP brand overall, which may, in part at least,
explain why HP showed 12 units that were high emitters. However, there
were something like 37 models that showed no emissions, and we still
don't know which brands were in that group. The manufacturers products
tested included HP, Canon, Toshiba, and Ricoh.


Art

 

[Michael Hopper]

This study is disconcerting, and important, since many of us work in
places with laser printers and photocopiers and some of us work on them
and their cartridges.

The abstract for the article is at http://tinyurl.com/2hns4s

You have to have a subscription to the journal to see the full PDF.
The abstract give less info than the press release.

My reason for questioning aftermarket cartridges is that the toner
used in those does is not always checked for particle size
distribution as carefully as the OEM toner and the aftermarket has
much more troubles blending on the very fine charge and transfer
control additives (silica, titania and alumina) onto the toner
surface. As you mention carbon black can be a problem unless the
toner maker has gone to great lengths to minimize its mutagenic
effects (usually surface chemicals).

Mike

 

[Burt]

This study is disconcerting, and important, since many of us work in
places with laser printers and photocopiers and some of us work on them
and their cartridges.

They studied 62 models of which 17 were considered high emitters.

They mention that 12 HP models and one Toshiba were in that high emitter
class. That's 13 of them, so there were 4 more, as well. I assume they
were probably newer models, but I don't know. I have not been able to
find the original article which lists all of the printers and their
emission levels.

I'm not sure one can assume remanufacturered or third party cartridges are
worse than OEM. The problem is the smaller the size of the toner
particles, the greater the risk of the particles entering the blood
stream, and also the greater risk of them being breathed in, and since
typically smaller particles provide higher print quality, it may be that
the higher quality may be from OEM products. Many laser printer companies
are quite proud to advertise that they have very small toner particle
sizes.

I would say that those of us who work with toner cartridges and laser
printers mechanically or with refilling are at greatest risk, however.

I think I best start wearing a face mask more regularly based upon this.

If anyone comes across the actual article, please post the link.

Art

(snip)

Try this link, Art. this article was in the San Francisco Chronicle today
and did list printers as high, medium, and low emitters.
http://www.sfgate.com/cgi-bin/article.cgi?file=/c/a/2007/08/01/MNFBRAN0J2.DTL

 

[Tony]

(snip)

Try this link, Art. this article was in the San Francisco Chronicle today
and did list printers as high, medium, and low emitters.
http://www.sfgate.com/cgi-bin/article.cgi?file=/c/a/2007/08/01/MNFBRAN0J2.DTL

Burt
This is a very interesting study but clearly there is much more work to be done
before any valid conclusions can be drawn.
I refer to the full article at
http://cdn.sfgate.com/chronicle/acrobat/2007/08/01/printer_es063049z.pdf which
the link you kindly provided led me to. HP of course have the lions share of
the laser printer market and that is why so many of their printers appear on
the list.
Several printers appear both in the Non-emitter and the High Level Emitter
columns on page D. The article states that this needs more research but to add
more focus to this it is worthwhile pointing out that the LJ5si and the LJ8000
and the LJ8150 are essentially the same print engine, as are the LJ4plus and
the LJ5N and the LJ5. In fact there are several laser engines that appear both
in the worst and best columns, this paradox needs to be researched before any
valuable lessons can be learned.
It seems to me that a couple of highly skilled and no doubt well respected
scientists have done some potentially worthwhile research and have published
the results but are not yet able to provide any evidence of a link to disease
or damage. They may of course do this in the future and I will be amongst the
first to take note and action if such a link exists.
One small point occurred to me when reading the report, and this in no way
invalidates the research, most (perhaps all) of the HP printers have engines
built by Canon, the only difference between a Canon engine and the HP printer
using that engine is a circuit board interface printed and the printer
covers....Not sure why that amused me, but it did!
I shall watch this develop with great interest but at this time the most
important questions for me are -
1. Why do several engines appear in both the best and worst performers?
2. What damage do the emissions do?
3. Did they look at the source of the toner cartridges, I am aware that for a
particular printer cartridges are built in different countries?
I am sure many will be watching this issue but I for one will not be holding my
breath, pun intended.
Tony

 

[Burt]

Burt
This is a very interesting study but clearly there is much more work to be
done
before any valid conclusions can be drawn.
I refer to the full article at
http://cdn.sfgate.com/chronicle/acrobat/2007/08/01/printer_es063049z.pdf
which
the link you kindly provided led me to. HP of course have the lions share
of
the laser printer market and that is why so many of their printers appear
on
the list.
Several printers appear both in the Non-emitter and the High Level Emitter
columns on page D. The article states that this needs more research but to
add
more focus to this it is worthwhile pointing out that the LJ5si and the
LJ8000
and the LJ8150 are essentially the same print engine, as are the LJ4plus
and
the LJ5N and the LJ5. In fact there are several laser engines that appear
both
in the worst and best columns, this paradox needs to be researched before
any
valuable lessons can be learned.
It seems to me that a couple of highly skilled and no doubt well respected
scientists have done some potentially worthwhile research and have
published
the results but are not yet able to provide any evidence of a link to
disease
or damage. They may of course do this in the future and I will be amongst
the
first to take note and action if such a link exists.
One small point occurred to me when reading the report, and this in no way
invalidates the research, most (perhaps all) of the HP printers have
engines
built by Canon, the only difference between a Canon engine and the HP
printer
using that engine is a circuit board interface printed and the printer
covers....Not sure why that amused me, but it did!
I shall watch this develop with great interest but at this time the most
important questions for me are -
1. Why do several engines appear in both the best and worst performers?
2. What damage do the emissions do?
3. Did they look at the source of the toner cartridges, I am aware that
for a
particular printer cartridges are built in different countries?
I am sure many will be watching this issue but I for one will not be
holding my
breath, pun intended.
Tony

Tony - Two printers with the same engine may have the "box" in which they
are installed better sealed. Just an uneducated guess.

 

[Arthur Entlich]

Hi Michael,

Thanks for the link, and the thoughts about OEM versus 3rd party toner
components. I don't think the study went into the details of what toner
types were in use, at least none of the summary articles stated so.

I have gleaned a few more pieces of information regarding the study,
however:

A total of 62 laser printers of varying ages were tests. There was some
repetition of models, so 42 unique models were involved.

The majority (34) were HP brand units
only 5 were Ricoh, 2 were Toshiba and 1 was Canon.

60% showed no emission of particulate materials.

40% showed some emission, or which 27% were considered high.

18 HP models were non-emitting, leaving 16 as having some emissions

One of the two Toshiba was a high emitter, the Studio 450 model.

The Canon IRC6800 was a low emitter, as was the Ricoh CL3000DN.

HP Laserjet 5M was a low emitter, while the HP Laserjet 1020 was a
medium emitter and the HP Laserjet 1320n was a high emitter.

In color, the HO Color laser 4550DN was a NON-emitter, but the HP
Colorlaser 4650DM was a high emitter.

Older models tended to release less but the particles were smaller.
This surprised me as most newer toners are ground smaller.

I'll continue looking for more complete results of this study and report
here on what I find.

Art

 

[Arthur Entlich]

Hi Burt,

Thanks for that link, which is the most complete I have been able to
access today.

For those who do not have the opportunity to look at the link, here is
the list. The HP models make up the majority in all classes, seeming to
indicate it is quite model specific:

High-level emitters

HP Color LaserJet 4650dn
HP Color LaserJet 5550dtn
HP Color LaserJet 8550N
HP LaserJet 1320N
HP LaserJet 1320n
HP LaserJet 2420dn
*HP LaserJet 4200dtn
HP LaserJet 4250n (old cartridge)
HP LaserJet 4250n (new cartridge)
HP LaserJet 5(a) (further study needed)
*HP LaserJet 8000DN
HP LaserJet 8150N
Toshiba Studio 450

Mid-level emitters

HP LaserJet 1020
HP LaserJet 4200dtn

Low-level emitters

Canon IRC6800
HP LaserJet 5M
HP LaserJet 9000dn
Ricoh CL3000DN

Non-emitters

HP Color LaserJet 4550DN
HP Color LaserJet 8500DN
HP LaserJet 2200DN
HP LaserJet 2300dtn
HP LaserJet 4 plus
HP LaserJet 4000N
HP LaserJet 4000TN
HP LaserJet 4050N
HP LaserJet 4050TN
HP LaserJet 4si
HP LaserJet 5(b) (further study needed)
HP LaserJet 5000n
HP LaserJet 5100tn
HP LaserJet 5N
HP LaserJet 5si
HP LaserJet 5si/NX
HP LaserJet 8000DN
HP LaserJet 8150DN
Ricoh Aficio 2022
Ricoh Aficio 3045
Ricoh Aficio 3245C
Ricoh Aficio CC3000DN
Toshiba Studio 350

*possible high emitter


Art

 

[Bob Headrick]

Hi Burt,

Thanks for that link, which is the most complete I have been able to
access today.

For those who do not have the opportunity to look at the link, here is the
list. The HP models make up the majority in all classes, seeming to
indicate it is quite model specific:

The study had lots of HP models because the building they happened to
measure had a lot of HP printers. They studied all the printers in one
particular office building, it was not a study that made an attempt to
compare various models. As others have mentioned some models fall in both
the high and low categories. No mention is made of the types of cartridges
(OEM or otherwise), age of the printers (either years or pages) or any
maintenance history. It may be "typical" or not. Some of the printer
models are a dozen years old. Certainly there will be more studies.

- Bob Headrick

 

[Arthur Entlich]

I agree that the study is very preliminary and as you state, it has a
lot of factors which were not controlled for. I think what can best be
drawn from this is that some laser printers tend to emit particles and
some don't, but which and why is unclear. It could be cartridge styles,
type of toner, age of toner cartridge or printer, model or design,
amount of use, etc.

The people involved in the study seem to be well versed in issues of
particle contamination in an indoor settings, but I think they need some
better understanding of laser printer technology to find the causes and
remedies.

Art

 

[NotMe]

|I agree that the study is very preliminary and as you state, it has a
| lot of factors which were not controlled for. I think what can best be
| drawn from this is that some laser printers tend to emit particles and
| some don't, but which and why is unclear. It could be cartridge styles,
| type of toner, age of toner cartridge or printer, model or design,
| amount of use, etc.
|
| The people involved in the study seem to be well versed in issues of
| particle contamination in an indoor settings, but I think they need some
| better understanding of laser printer technology to find the causes and
| remedies.

Having considerable experience with clean rooms my first recommendation
would be to employ localized electrostatic filters near the machines. Second
would be to have electrostatic filtering in the HVAC system as even the
house hold models pull down to < 2 microns particle size.

 

[Michael Hopper]

Having considerable experience with clean rooms my first recommendation
would be to employ localized electrostatic filters near the machines. Second
would be to have electrostatic filtering in the HVAC system as even the
house hold models pull down to < 2 microns particle size.

According to the paper in Environmental Health and Safety the
particles they measured were mostly smaller than 1 micron in diameter
and had a peak in number at about 0.2 microns; almost an order of
magnitude smaller than the number you quote.

Such small particles should not be whole toners but are most like
additives (silica, alumina and titania)that were blended onto the
toner surface to give the powder adequate flow and charging
characteristics.

Mike

 

[NotMe]

|
| >
| > Having considerable experience with clean rooms my first recommendation
| > would be to employ localized electrostatic filters near the machines.
Second
| > would be to have electrostatic filtering in the HVAC system as even the
| > house hold models pull down to < 2 microns particle size.
|
| According to the paper in Environmental Health and Safety the
| particles they measured were mostly smaller than 1 micron in diameter
| and had a peak in number at about 0.2 microns; almost an order of
| magnitude smaller than the number you quote.
|
| Such small particles should not be whole toners but are most like
| additives (silica, alumina and titania)that were blended onto the
| toner surface to give the powder adequate flow and charging
| characteristics.

The 2 micro rating is based on 100% filtering which covers 99% of the
requirements for home systems (viruses are typically > 2 micros). Home
systems will pull out smaller particles epically if the fan speeds are
reduced but the specks don't reflect this as the market has not cared.

I have not had time to investigate more on this subject but I would expect
the contamination level to be greatly reduced even with the simplest of
standard home type electrostatic filters.